Disk playback with clamping mechanism and misalignment detector

ABSTRACT

A disk playback device holds a disk in a playback position. A turntable moves toward the disk to a raised position where its support surface is adjacent a back of the disk. A spindle inserts through a center hole of the disk to align the disk with the turntable. A clamper is held above the disk on a side of the disk opposite the turntable. The clamper is supported close enough to the disk that when the turntable is in the raised position, a magnet in the turntable exerts a substantial force on a piece of ferromagnetic material in the clamper. When the clamper is released it clamps the disk to the turntable. By bringing the clamper and turntable to the disk rather than moving the disk toward one or the other, no space is required for the displacement of the disk in a direction perpendicular to its surface. The clamper is supported by a pair of holders, slidable in a direction parallel to the surface of the disk. Wedge-shaped surfaces on the holders engage a flange on top of the clamper to lift and hold the clamper above the disk. If a disk is misaligned with the spindle when the turntable is brought to the raised position, the disk is pressed against the clamper. The clamper in turn presses against inclined surfaces of the holders causing the holders to spread apart. The spreading is detected to invoke a control routine to correct the misalignment.

BACKGROUND OF THE INVENTION

The present invention relates to a recorded disk playback device, suchas a CD player, and specifically to such a device as employs a clamperto clamp the disk onto a turntable.

Disk players that employ a turntable to rotate recorded disks forplayback are known. Some known devices transport the disk to a playbackposition and then lift the disk out of its support, for example a tray,toward a rotatable clamp. The clamp has a magnet that is attracted tothe turntable surface. The turntable continues to move upward, carryingthe disk off its support (eg. surface of the tray), until it is closeenough to cause the clamp to settle against the disk, thereby securingit to the turntable. This moves the disk away from the mounting surfaceof the tray, and the magnet arranged in the clamper is attracted to theturntable. In this way the disk is clamped between the turntable and theclamp so that the turntable can rotate the disk.

One problem with the type of device described above is that asubstantial amount of space is required to permit the disk to moveupward perpendicular to its surface. Since compactness is usually animportant design goal for such devices, this space requirement isundesirable. For example, to make a CD player for a computer that fitsinto the standard form factor for peripherals, space is difficult tofind. Any refinements to avoid the space requirement, such as by keepingthe disk in place and moving the clamping elements toward it, would addcomplexity and cost to the design as well as introduce additional spacerequirements.

OBJECT AND SUMMARY OF THE INVENTION

It is an object of the invention is to overcome the drawbacks of theprior art.

It is an object of the invention to provide a disk player that iscompact.

It is an object of the invention to provide a disk player that can bemanufactured for a low cost.

It is an object of the invention to provide a disk player in which adisk does not need to be displaced in a direction perpendicular to itssurface to clamp the disk to a turntable.

Briefly, a disk playback device holds a disk in a playback position. Aturntable moves toward the disk to a raised position where its supportsurface is adjacent a back of the disk. A spindle inserts through acenter hole of the disk to align the disk with the turntable. A clamperis held above the disk on a side of the disk opposite the turntable. Theclamper is supported close enough to the disk that when the turntable isin the raised position, a magnet in the turntable exerts a substantialforce on a piece of ferromagnetic material in the clamper. When theclamper is released it clamps the disk to the turntable. By bringing theclamper and turntable to the disk rather than moving the disk toward oneor the other, no space is required for the displacement of the disk in adirection perpendicular to its surface. The clamper is supported by apair of holders, slidable in a direction parallel to the surface of thedisk. Wedge-shaped surfaces on the holders engage a flange on top of theclamper to lift and hold the clamper above the disk. If a disk ismisaligned with the spindle when the turntable is brought to the raisedposition, the disk is pressed against the clamper. The clamper in turnpresses against inclined surfaces of the holders causing the holders tospread apart. The spreading is detected to invoke a control routine tocorrect the misalignment. The features of the clamping mechanism avoidthe need for vertical movement for the recording surface of the diskduring the clamping operation. Also, clamper movement is effected merelyby releasing the support for the clamper. This helps to make the devicemore compact, and less expensive to manufacture.

According to an embodiment of the present invention, there is described,a disk player, comprising: a chassis having a playback position in fixedrelation thereto, means, connected to the chassis, for supporting a diskin the playback position, means for releasing the disk in the playbackposition, whereby the disk is unsupported by the means for supporting, aturntable, connected to the chassis so that the turntable is movable ina first direction toward the disk in the playback position, first meansfor moving the turntable in the first direction toward the disk in theplayback position, a clamper, for pressing the disk against theturntable, movably connected to the chassis and second means for movingthe clamper toward the disk in the playback position in a directionopposite the first direction.

According to another embodiment of the present invention, there isdescribed, a disk playback device for playing back a disk, comprising: achassis, the disk having a recording surface and a back surface, asupported in a disk in a playback position of the disk playback device,the disk being in an orientation in which the recording surface faces ina first direction, the playback position being in fixed relation to thechassis, a turntable, movably connected to the chassis, having a supportsurface, means for holding the turntable in a first position towardwhich the back surface faces when the disk is supported in the playbackposition, means for moving the turntable in the first direction to asecond position whereat the support surface contacts the back surface, aclamper having a clamping surface, means for supporting the clamper sothat the first surface is held away from the recording surface and meansfor moving the clamper toward the recording surface and urging theclamper surface against the recording surface when the turntable is inthe second position, whereby the disk is frictionally engaged with theturntable surface.

According to still another embodiment of the present invention, there isdescribed, a disk playback device, comprising: a turntable having a diskmounted thereon, a clamper, on a side of the disk opposite theturntable, for clamping the disk to the turntable, supporting means forsupporting the clamper at a first position away from the disk prior to aclamping of the disk and the supporting means including means forreleasing the clamper, whereby the clamper is freed to move toward thedisk.

The above, and other objects, features and advantages of the presentinvention will become apparent from the following description read inconjunction with the accompanying drawings, in which like referencenumerals designate the same elements.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view of a main chassis of a disk player.

FIG. 2 is an exploded view of a support mechanism of a disk transfermechanism, a clamper support mechanism, a disk clamper, and a disk lockmechanism, all attached to a loading chassis 80 of the main chassis ofFIG. 1.

FIG. 3 is an exploded view of a drive-side disk guide of the disktransfer mechanism of FIG. 2.

FIG. 4 is an exploded view of a fixed disk guide of the disk transfermechanism of FIG. 2.

FIG. 5 is an end-wise cross-section of the drive-side disk guide of FIG.3.

FIG. 6 is an end-wise cross-section of the fixed disk guide of FIG. 4.

FIG. 7 is an exploded view of a loading plate opening/closing mechanismof the disk transport mechanism of FIG. 2.

FIG. 8 is a top-wise cross-section of the fixed disk guide of FIGS. 4and 6.

FIG. 9 is an exploded view of an optical mechanism and clamper lockmechanism.

FIG. 10 is an exploded view of an optical mechanism vertical transfermechanism of the optical mechanism of FIG. 9.

FIG. 11 is an exploded view of a stocker and stocker vertical transfermechanism.

FIG. 12 is an exploded view of a disk lock mechanism.

FIG. 13 is a top-view of the disk transfer mechanism of FIG. 2 in a diskreceiving position.

FIG. 14 is a top-view of the disk transfer mechanism of FIG. 2 with adisk in an initial stage of a disk loading operation for alarge-diameter disk.

FIG. 15 is a top-view of the disk transfer mechanism of FIG. 2 in alater stage of the disk loading operation for a large-diameter disk.

FIG. 16 is a top-view of the disk transfer mechanism of FIG. 2 in whicha large-diameter disk is firmly held in an intermediate position, inwhich it is supported by the disk transfer mechanism, and in a playbackposition.

FIG. 17 is a top-view of the disk transfer mechanism of FIG. 2 showing alarge-diameter disk released in the playback position in preparation forplaying the disk back.

FIG. 18 is a top-view of the disk transfer mechanism of FIG. 2 showing alarge-diameter disk in a store position.

FIG. 19 is a top-view of the disk transfer mechanism of FIG. 2 showing asequence of disk outlines indicating positions occupied by alarge-diameter disk being moved from the store position to and ejectposition.

FIG. 20 is a top-view of the disk transfer mechanism of FIG. 2, with asmall-diameter disk during insertion.

FIG. 21 is a top-view of the disk transfer mechanism of FIG. 2 in whicha small-diameter disk is firmly held in a intermediate position, inwhich it is supported by the disk transfer mechanism, and in a playbackposition.

FIG. 22 is a top-view of the disk transfer mechanism of FIG. 2 showing asmall-diameter disk released in the playback position in preparation forplaying the disk back.

FIG. 23 is a top-view of the disk transfer mechanism of FIG. 2 showing asmall-diameter disk in a store position.

FIG. 24 is a top-view of the disk transfer mechanism of FIG. 2 showing asequence of disk outlines indicating positions occupied by asmall-diameter disk being moved from the store position to and ejectposition.

FIG. 25 is a top-view of the loading plate opening/closing mechanismwith a sliding plate mechanism in a first position.

FIG. 26 is a top-view of the loading plate opening/closing mechanismwith a sliding plate mechanism in a second position.

FIG. 27 is a top-view of the loading plate opening/closing mechanismwith a sliding plate mechanism in a third position.

FIG. 28 is a top-view of the loading plate opening/closing mechanismwith a sliding plate mechanism in a fourth position which engages a rackmember.

FIG. 29 is a top-view of the loading plate opening/closing mechanismwith a sliding plate mechanism in a fifth position which engages therack member and which a pinion has traveled a distance on the rackmember to open the loading plate opening/closing mechanism.

FIG. 30 is a top-view of the clamper lock mechanism in which the slidingplate mechanism is in a first position in which the clamper lockmechanism remains in a locked position.

FIG. 31 is a top-view of the clamper lock mechanism in which the slidingplate mechanism is in a second position in which the clamper lockmechanism remains in a locked position.

FIG. 32 is a top-view of the clamper lock mechanism in which the slidingplate mechanism is in a third position in which the clamper lockmechanism remains in a locked position.

FIG. 33 is a top-view of the clamper lock mechanism in which the slidingplate mechanism is in a fourth position in which the clamper lockmechanism is moved to an unlocked position.

FIG. 34 is a top-view of optical mechanism vertical transfer mechanismwhere the sliding plate mechanism is in the first state in which theoptical mechanism is lowered.

FIG. 35 is an end-view of optical mechanism vertical transfer mechanismwhere the sliding plate mechanism is in the first state in which theoptical mechanism is lowered.

FIG. 36 is a top-view of optical mechanism vertical transfer mechanismwhere the sliding plate mechanism is in the second state in which theoptical mechanism is lowered.

FIG. 37 is a end-view of optical mechanism vertical transfer mechanismwhere the sliding plate mechanism is in the second state in which theoptical mechanism is lowered.

FIG. 38 is a top-view of optical mechanism vertical transfer mechanismwhere the sliding plate mechanism is in the third state in which theoptical mechanism is raised.

FIG. 39 is a top-view of optical mechanism vertical transfer mechanismwhere the sliding plate mechanism is in the third state in which theoptical mechanism is raised.

FIG. 40 is a top-view of optical mechanism vertical transfer mechanismwhere the sliding plate mechanism is in the fourth state in which theoptical mechanism is raised.

FIG. 41 is a top-view of optical mechanism vertical transfer mechanismwhere the sliding plate mechanism is in the fourth state in which theoptical mechanism is raised.

FIG. 42 is a top-view of the clamper support mechanism where the loadingplates are in a position for receiving a disk.

FIG. 43 is an end-wise section of the clamper support mechanism wherethe loading plates are the position shown in FIG. 42.

FIG. 44 is a top-view of the clamper support mechanism where the loadingplates are in a position in which a large-diameter disk is supported.

FIG. 45 is an end-wise section of the clamper support mechanism wherethe loading plates are the position shown in FIG. 44.

FIG. 46 is a top-view of the clamper support mechanism immediately afterthe optical mechanism and turntable have been raised to clamp the disk.

FIG. 47 is an end-wise section of the clamper support mechanism whereoptical mechanism and turntable are in the configuration of FIG. 46.

FIG. 48 is a top-view of the clamper support mechanism after the clamperhas been released.

FIG. 49 is an end-wise section of the clamper support mechanism in theconfiguration of FIG. 48.

FIG. 50 is an end-wise section showing the clamper support mechanismafter releasing the clamper while no disk is present between the clamperand the turntable.

FIG. 51 is an end-wise section of the clamper support mechanism after anattempted disk clamping of a misaligned disk

FIG. 52 is a top view of the disk lock mechanism with the sliding platemechanism in the first position in which the disks are locked.

FIG. 53 is a side section showing the disk lock mechanism with thesliding plate mechanism and the disk lock mechanisms in the position ofFIG. 52.

FIG. 54 is a top view of the disk lock mechanism with the sliding platemechanism in the second position in which a disk is unlocked.

FIG. 55 is a side section showing the disk lock mechanism with thesliding plate mechanism and disk lock mechanisms in the positions ofFIG. 54.

FIG. 56 is a top view of the disk lock mechanism with the sliding platemechanism in the third position in which the lock is partly closed.

FIG. 57 is a side section showing the disk lock mechanism with thesliding plate mechanism and disk lock mechanisms in the positions ofFIG. 56.

FIG. 58 is a top view of the disk lock mechanism with the sliding platemechanism in the fourth position in which a disks are locked.

FIG. 59 is a side section showing the disk lock mechanism with thesliding plate mechanism and disk lock mechanisms in the positions ofFIG. 58.

FIG. 60 is a top-view of a disk insertion error prevention mechanismprepared to allow insertion of a disk.

FIG. 61 is a partial section showing the disk insertion error preventionmechanism positioned as in FIG. 60.

FIG. 62 is a top-view of the disk insertion error prevention mechanismclosed after transport of a disk beyond a flap closure.

FIG. 63 is a partial section showing the disk insertion error preventionmechanism positioned as in FIG. 62.

FIG. 64 is a partial end section of the disk insertion error preventionmechanism during transport of a disk past the flap closure.

FIG. 65 is a timing chart indicating the relative states of the loadingplates, the clamper support mechanism, the flap closure and signals usedfor transporting a disk into the disk player.

FIG. 66 is a timing chart indicating the relative states of the clamperlock mechanism the rack and pinion mechanism used to open the loadingplates, the disk lock mechanism, the position of the optical mechanism,the position of the sliding plate and the state of a signal used toregister the sliding plate position.

FIG. 67 is a block diagram of a control circuit for the disk player.

FIG. 68 is a flowchart of a main procedure of system controller 300.

FIG. 69 is a flowchart of a JOB LOAD procedure.

FIG. 70 is a flowchart of the JOB LOAD procedure.

FIG. 71 is a flowchart of the JOB LOAD procedure.

FIG. 72 is a flowchart of a JOB EJECT procedure.

FIG. 73 is a flowchart of the JOB EJECT procedure.

FIG. 74 is a flowchart of the JOB EJECT procedure.

FIG. 75 is a flowchart of the JOB EJECT procedure.

FIG. 76 is a flowchart of the JOB EJECT procedure.

FIG. 77 is a flowchart of the JOB EJECT procedure.

FIG. 78 is a flowchart of the JOB EJECT procedure.

FIG. 79 is a flowchart of the JOB EJECT procedure.

FIG. 80 is a flowchart of the JOB STOCK procedure.

FIG. 81 is a flowchart of the JOB STOCK procedure.

FIG. 82 is a top-wise cross-section of drive-side disk guide 1002.

FIG. 83 is a cross-section of a second embodiment of the drive-side diskguide.

FIG. 84 is a cross-section of a third embodiment of the drive-side diskguide.

FIG. 85 is a cross-section of a fourth embodiment of the drive-side diskguide.

FIG. 86 is a perspective drawing indicating an alternative embodiment ofthe disk player in which the disk player is mounted vertically.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, a housing 1000 of a disk player conforms tostandard dimensions for computer peripherals having a 51/4 inchhalf-height form factor. Housing 1000 has outer dimensions, 41.5 mmheight×146 mm width×209 mm depth. The disk player includes a diskchanger that stores four Cds for selective playback. Housing 1000 isgenerally box-shaped with four sides, a lower panel, and a top cover 3.A loading chassis 80 is attached to integral mounting brackets of twosides of main chassis 90 between top cover 3 and the lower panel of mainchassis 90. Top cover 3 may be omitted when the disk player is mountedon a front panel of a computer (not shown in the drawings).

A front panel 1 is attached to a front one of the four sides of mainchassis 90. Front panel 1 has an insertion aperture 1A for receiving andejecting disks. Insertion aperture 1A is wider toward its center than atits ends. The shape of insertion aperture 1A insures that only the edgesof disks contact front panel 1 when disks are inserted and removed.Therefore, recording surfaces of disks are prevented from contactingfront panel 1, eliminating a potential cause of damage to disks duringinsertion and removal.

Referring to FIGS. 2-4, a disk transfer mechanism 1001 includes adrive-side disk guide 1002, slidably mounted on a lower side of loadingchassis 80 on a left side of housing 1000. A fixed-side disk guide 1003is slidably mounted on the lower side of loading chassis 80 toward aright side of housing 1000. L-shaped loading plates 81L and 81R hang onsupport pins 17A and 17B attached to their upper surfaces, respectively.Support pins 17A and 17B pass through respective transverse guidegrooves 80A and 80B in loading chassis 80. Rings 21A and 21B, at ends ofsupport pins 17A and 17B, respectively, prevent support pins 17A and 17Bfrom slipping out of guide grooves 80A and 80B. Fixed and drive-sidedisk guides 1003 and 1002 attach to L-shaped loading plates 81R and 81L,respectively, thereby permitting fixed and drive-side disk guides 1003and 1002, move transversely on the bottom of loading chassis 80.

Guide rollers 19A and 19B, rotatably mounted on upper surfaces ofloading plates 81L and 81R, travel in guide grooves 80A, 80B in loadingchassis 80. Guide rollers 19A, 19B fit closely within guide grooves 80A,80B. Thus, guide rollers 19A and 19B insure accurate alignment ofloading plates 81L and 81R throughout their respective ranges ofmovement. Support pins 17A are shorter than support pins 17B so thatloading plate 81R is guided at a position closer to loading chassis 80than loading plate 81L, permitting loading plates 81L and 81R tooverlap.

Respective opposing sides of loading plates 81L and 81R have integralracks 810L and 810R. A pinion gear 85, which rotates on the bottomsurface of loading chassis 80, engages with racks 810L and 810R. Whenloading plate 81L moves laterally, pinion gear 85 rotates in a directionthat forces loading plate 81R to move an equal distance in the oppositedirection of loading plate 81L. A spring 127 strung between a ring 21Bon an upper portion of support pin 17B of loading plate 81L and pin 21Con an upper surface of loading chassis 80, urges loading plates 81L and81R toward each other.

A bent portion of loading plate 81L forms an integral shutter piece 811in loading plate 81L toward the front of housing 1000. Shutter piece 811interrupts a light beam generated, and detected, by an optical sensor236 on the front end of loading chassis 80. Disks are supported betweenfixed and drive-side disk guides 1003 and 1002. Thus, the mutual spacingof fixed and drive-side disk guides 1003 and 1002 is determined by thewidth of the disk they support. Optical sensor 236 is positioned so thatthe light beam is broken when a disk of a certain size is supportedbetween timing and friction belts 14 and 12 respectively. Referring alsoto FIG. 65, a signal IN, which is output by optical sensor 236, goeshigh (H) when the size of an inserted disk is between 78 and 84 mm,which corresponds with small diameter compact disks.

Referring to FIGS. 3 and 5, drive-side disk guide 1002 includes an upperdisk guide 9 of a resin having a low friction coefficient such asDuracon. A lower surface of upper disk guide 9 forms an upper half of aguide groove 9', which guides the edge of the inserted disk on the leftside of housing 1000. A sloped surface 9A, with a slope of 45 degrees,runs longitudinally on a lower surface of upper disk guide 9. Aprojection 9B, on a bottom end of sloped surface 9A, engages the uppersurface of the disk edge. A sloped surface 10A, running longitudinallyon a lower disk guide 10, slopes at a 45-degree angle in a directionopposite that of sloped surface 9A. A projection 10B on an upper end ofsloped surface 10A engages a lower surface of the disk edge. A gap of1.3 mm width (H1), between projection 9B and projection 10B, is slightlywider than the thickness of a disk (1.2 mm) so that the disk edge isguided precisely.

Referring to FIG. 3, a timing pulley 15 rotates on a shaft 16 on aforward end of upper disk guide 9. Shaft 16 projects through the lowersurface of upper disk guide 9. Another shaft 6 projects upwardly fromthe upper surface of lower disk guide 10 at its rear end. Another timingpulley 7 rotates on shaft 6. A timing belt 14 is stretched betweentiming pulleys 15 and 7 to form a loop with a long axis of the loopbeing parallel to a direction of transport of disk D, d. An insidesurface of timing belt 14 has teeth or serrations. Outside surfaces oftiming pulleys 15 and 7, adjacent corresponding portions of the insidesurface of timing belt 14, also have teeth or serrations to engage theteeth or serrations of timing belt 14, thereby preventing slippage oftiming belt 14 with respect to timing pulleys 15 and 7.

Referring, now to FIGS. 4 and 6, a fixed-side disk guide 1003 supportsfriction belt 12. As in drive-side disk guide 1002, fixed-side diskguide 1003 has a disk guide 11 of a resin material having a low frictioncoefficient. A guide groove 11' is formed longitudinally on disk guide11 to guide the disk edge opposite drive-side disk guide 1002. Guidegroove 11' includes sloping surfaces 11A, 11B, and a square U-shapedgroove 11C that form a channel shape with a tapered entry.

Referring now also to FIG. 8, a tapered disk guide 11E is mounted towarda front end of fixed-side disk guide 1003. A gap H2 of groove 11C is 1.5mm wide, slightly wider than the thickness of a disk. This gap widthallows the disk edge to be guided precisely without binding. Frictionbelt 12 is fixed to a flat wall 11D of a belt fixing piece 11F at theblind end of groove 11C. Friction belt 12 runs the length of fixed-sidedisk guide 1003 except for the front portion over which disk guide 11Eextends. Friction belt 12 has a high friction coefficient to prevent therim of the disk from slipping. Ends 12A of friction belt 12 are wrappedaround belt fixing piece 11F and held in place by a reinforcement plate13. Reinforcement plate 13 also supports flat wall 11D to prevent itfrom bowing due to the force applied by the disk running along frictionbelt 12.

Referring to FIG. 3, 5, and 6 an outer perimeter surface 14A of timingbelt 14 is positioned to engage with the disk edge, guided betweenprojections 9B, 10B, on the left side of housing 1000. Friction belt 12engages the opposite edge of the disk. Timing belt 14 is revolved bytiming pulley 15 to move the disk inside housing 1000. Friction belt 12is fixed relative to loading plate 81R. Therefore, if timing belt 14were permitted to bow, the center of the disk would move toward the leftof the device causing the path of the disk to be nonlinear. Also, thedistance of disk transfer, from front to rear, is determined from theangular displacement of timing pulley 15. The non-linear displacement ofthe disk would make it difficult to determine the fore-aft displacementof the disk from the angular displacement of timing pulley 15. This isso because, with bowing of timing belt 14 and friction in the slidingsupports, the transverse movement of the disk would be a complexfunction of fore-aft displacement of timing pulley 15 which would varywith properties of the timing belt (which could also change over time).Therefore any bowing in timing belt 14 is likely to lead to errors infore-aft position detection of the disk.

Referring momentarily to FIG. 82, timing belt 14 is prevented frombowing by a guide wall 10D, on lower disk guide 10. The inside surface14B of timing belt 14 slides over guide wall 10D. This prevents theforce of the disk from pressing timing belt 14 inwardly. A metal plate8, between disk guide 9 and disk guide 10, reinforces disk guides 9 and10. Since disk guides 9 and 10 are of resin, metal plate 8 prevents diskguides 9 and 10 from flexing. A disk protection sheet 23, attached tothe top and bottom surfaces of the rear side of disk guides 9, 10,prevent damage to stored disks (described later) above and below diskguide 9.

Referring now to FIG. 7, a loading plate open/close mechanism 1004,rotates timing pulley 15. Motor 250 is fixedly attached to main chassis90 on a bracket 180. A worm gear 253 is press-fitted to a rotating shaftof drive motor 250. A gear member 63 rotates on shaft 91 attached tomain chassis 90. Gear 63A on a lower portion of gear member 63, engagesworm gear 253. Plate 86A is fixed to a shaft 88 which fits in a centerhole 91A of shaft 91, allowing plate 86A to swing freely. A gear 82Brotates on a shaft hingeably interconnecting plates 86A and 86B. Timingpulley 15 rotates on shaft 16 protruding from a distal end of plate 86B.An intermediate gear 82C, rotating at a middle of plate 86A, meshes withboth gear 63C, on an upper portion of gear member 63, and gear 82B,thereby transmitting rotation of the shaft of motor 250 to gear 82B.Rotation of gear 82B is further transmitted to timing pulley 15 by agear 82A that rotates on a middle of plate 86B. Gear 82A meshes withgear 82B and a gear 15B on a lower portion of timing pulley 15.

Referring momentarily to FIGS. 25-29, plates 86A, 86B pivot responsivelythe position of timing pulley 15 as timing pulley 15 moves transverselywith drive-side disk guide 1002. Thus, the rotation of motor 250 istransmitted to timing pulley 15 by an extensible transmission withoutmoving motor 250. With such an extensible transmission, there is no needfor space for movement of a bulky motor. In addition, by having anextensible transmission instead of a movable motor and transmission, themass and weight of the drive mechanism travelling with loading plate 81Lis minimized, making it possible to use a weaker spring 127 to urgeloading plates 81L and 81R medially together. Disk insertion is therebymade easier and more responsive. In addition, the pressure load ontiming belt 14 and friction belt 12 is reduced.

Optical sensor 232 is attached to a bend 180A in a bracket 180. Ashutter wheel 63B on the upper portion of gear member 63 periodicallyinterrupts a light beam detected by optical sensor 232 as gear member 63rotates. Optical sensor 232 generates a loading pulse signal, signal L.PULSE. Because bowing of the timing belt 14 is prevented as discussedabove, rotation of shutter wheel 63B is correlated in a predeterminedway with movement of disk D, d. Therefore, signal L. PULSE can serve asan indication of disk movement. During disk transfer, one pulse insignal L. PULSE indicates a movement of 0.5 mm of the disk in thepresent embodiment. The same signal L. PULSE also indicates the distancemoved by loading plate 81L during an operation that is described below.In this operation, one pulse indicates that loading plate 81L has moved0.314 mm.

Referring now also to FIG. 13, when no disk is held between drive-sideand fixed-side disk guide 1002 and 1003, the force of spring 127 pullssupport pins 17A and 17B together until they rest against the ends ofguide grooves 80A and 80B, respectively. This places disk transfermechanism 1001 in a disk receiving position (POS. 1). In the diskreceiving position, loading plates 81L and 81R, attached to support pins17A and 17B, respectively, are located at specified positions. Thespecified positions are such that the distance W1 between timing belt 14and friction belt 12, which are supported by loading plates 81L and 81R,is 76 mm. This separation distance is slightly smaller than the 80 mmdiameter of small-diameter disks. When disk transfer mechanism 1001 isin the disk receiving position, timing belt 14 is stationary and remainsso until a disk D, d is inserted a certain distance.

Referring to FIGS. 13-16, when disk D, d is inserted through insertionaperture 1A, the rim of disk D, d first engages with timing belt 14 anddisk guide 11E. As described above, disk guide 11E is of a resinmaterial having a low friction coefficient. Thus, the disk rim slidesfreely against disk guide 11E during disk insertion. As the disk isinserted, loading plates 81L and 81R are forced apart against the forceof spring 127. When disk D is inserted to the position indicated by P0,the separation distance between timing belt 14 and friction belt 12 isincreased to 78 mm. This initiates disk loading.

To pull disk D inside the device, disk transfer mechanism 1001 movestiming belt 14 counterclockwise. However, unless disk D is inserted asufficient distance, disk edge De will slide against disk guide 11E anddisk D will not be drawn in. This configuration requires the user topush the disk into the disk player until disk transfer mechanism 1001begins active transport. In general, the user will insert disk D intothe device by supporting disk spindle hole Ds and disk edge De with theforefinger and the thumb of the right hand. The right hand holding diskD naturally tends to turn clockwise as the forefinger releases disk Dand the thumb follows the left side edge De of disk De into the diskplayer, pushing gently with the thumb. Once disk transfer mechanism 1001begins active transport, the sensation felt by a right handed user isquite natural as the disk is pulled away from the thumb, because thedisk D rotates in a clockwise direction as it is transported in.

The presence of disk guide 11E and its location with respect to aright-handed user inserting a disk in a disk player located to theuser's right, help to protect friction belt 12 and timing belt 14 fromwear as follows. Timing belt 14 begins moving almost immediately afterthe disk is inserted (recall that only 2 mm additional separation isrequired to activate driving of timing belt 14). Thus, the left edge ofdisk D begins advancing into the disk player, immediately after a smallseparation of loading plates 81L and 81R, as timing belt 14 on the leftside starts moving. Even though the user may push disk D inwardly fasterthan timing belt 14 advances, the right side of disk D can slip easilyagainst the surface of disk guide 11E. A right-handed user with the diskplayer located to the user's right for easy access naturally tends topush against fixed-side disk guide 1003 rather than drive-side diskguide 1002. However, disk guide 11E is located on the right side to bearthe force of this pushing. The force applied to disk guide 11E helps toseparate fixed- and drive-side disk guides 1002 and 1003. In fact, it ispossible for almost no force to be born by timing belt 14 during themanual phase of disk insertion. In addition, it is evident that diskguide 11E also protects friction belt 12 as well. Thus, the presence ofdisk guide 11E prevents disk D from rubbing against timing belt 14 andfriction belt 12 during the initial phase of insertion. By preventingthe disk from rubbing against timing belt 14 and friction belt 12,damage and wear to timing belt 14 and friction belt 12 is minimized.

Once disk transfer mechanism 1001 has brought disk D to a position whereit is firmly supported between timing belt 14 and friction belt 12, diskD is moved independently of the user. Disk D is brought to a playbackposition (P2) and then to a stock position (P3). Referring momentarilyto FIG. 19, by driving timing belt 14 clockwise, disk transfer mechanism1001 brings disk D from a stock position (P3), or a playback position(P2), to an eject position (P4) where disk D, d may be removed by theuser. Disk transfer mechanism 1001 is controller to bring disk D as farto the front of the disk player as possible without causing permittingtiming belt 14 and friction belt 12 to lose their grip on it. That is,timing belt 14 is stopped just before timing belt 14 and friction belt12 would shift medially under the force of spring 127. This insures thatdisk D is firmly held in the eject position. The disk D is moved betweenthe eject position, the playback position, and the stock position inresponse to keypad entries by the user.

Referring momentarily to FIGS. 13, 17, and 25 when a disk is playedback, loading plates 81L and 81R are separated by a distance greaterthan the diameter of the disk, thereby releasing the disk so that thedisk can be rotated freely. A rack engager 1005, which moves loadingplates 81L and 81R apart, is also driven by motor 250.

Referring again to FIG. 7, a rack release plate 134 is attached to mainchassis 90 by pins 135, inserted in a guide grooves 90H in main chassis90, so that rack release plate 134 can slide left and right relative tomain chassis 90. A bend 134B in rack release plate 134 is positioned toengage a bend 75E in a sliding plate 75. A T-shaped rack release lever130 rotates on a shaft 133 extending from the upper surface of a motorbracket 180. A spring 138, strung between rack release lever 130 andmotor bracket 180, urges rack release lever 130 in a clockwisedirection, as viewed from above. An arm 130B of rack release lever 130passes through an opening 87C in a rack member 87, inserting into agroove 134A of rack release plate 134, so that rack release lever 130rotates counterclockwise responsively to a rightward movement of rackrelease plate 134.

Referring now also to FIG. 29, projections 87A on the lower end of rackmember 87, are inserted into holes (hidden in the drawing) in mainchassis 90. Rack member 87 has an integral rack 87D with a longitudinalaxis that runs laterally. The insertion of projections 87A into theholes forms a pivotable connection between rack member 87 and mainchassis 90 permitting rack member 87 to pivot in an arc whose tangentsare perpendicular to the axis of rack 87D. Thus, rack member 87 pivotstoward and away from the front of the disk player. Integral rack 87Dengages with gear 15C located between gears 15A and 15B timing pulley15. A bend 87B of rack member 87 is connected to arm 130A of rackrelease lever 130 by a plate 131 and a spring 132. When rack releaselever 130 rotates in a counterclockwise direction, rack member 87rotates toward the rear of the disk player causing rack 87D to mesh withgear 15C.

Referring now to FIGS. 7, 25-29, and 66, rack engager 1005 controls rackmember 87 so that it engages with gear 15C (ON) or disengages (OFF) inresponse to the position of sliding plate 75. While sliding plate 75 ismoving between a position DOWN-2 and a position UP-1, bend 75E ofsliding plate 75 is positioned at a distance from bend 134B of rackrelease plate 134. Therefore, in this range of positions, the force ofspring 138 rotates rack release lever 130 to position rack release plate134 toward the left end with pins 135, 135 resting at the left-most endsof their respective guide grooves 90H, 90H. In this range of positionsof sliding plate 75, rack member 87 is held away from gear 15C by plate131 as shown in FIGS. 25-27 under the urging of spring 138. When slidingplate 75 moves from position UP-1 to position UP-2, bend 75E engageswith bend 134B, and rack release plate 134 is moved to the right of thedisk player. Therefore, rack release plate 134 rotates rack releaselever 130 counterclockwise against the urging of spring 138 causingplate 131 and spring 132, to pull rack member 87 to a position whererack 87D meshes with gear 15C. Thus as sliding plate 75 approachesposition UP-2 form position UP-1 as timing pulley 15 is rotated, gear15C rotates so that it follows along rack 87D as shown in FIG. 29. Thiscauses loading plates 81L and 81R to move laterally between positions inwhich a disk is held between timing belt 14 and friction belt 12 to openpositions POS. 4, in which the disk is released (Compare FIGS. 13 and17).

Referring to FIGS. 9 and 49, an optical mechanism 1006 includes achassis 30, a turntable 102, an optical pickup 2, and an optical pickuptransfer mechanism 53. Disk D is mounted on turntable 102 and rotated asdisk D is played back. Turntable 102 has a gear 37 attached to its lowersurface. Turntable 102 and gear 37 are fixedly attached to the rotatingshaft of a main motor 33A which drives them. Gear 37 meshes with gear 35which, in turn, meshes with gear 36 of auxiliary motor 33B. Gear 35rotates on a shaft attached to chassis 30. Turntable 102 is thus rotatedby both main motor 33A and auxiliary motor 33B.

Main motor 33A and auxiliary motor 33B are both employed to driveturntable 102 during playback and to drive optical pickup 2 andturntable 102 during accessing and start-up operations described furtherbelow. Two motors are used because their operational combinationprovides certain benefits. During disk playback, motor 33A and auxiliarymotor 33B are supplied with drive voltage at a ratio of approximately7:3 so that auxiliary motor 33B acts as a load on main motor 33A. Theload of auxiliary motor 33B eliminates backlash between meshed gears35-37, minimizing vibration of turntable 102. Advantageously, becauseauxiliary motor 33B is partially driven by main motor 33A, a back-emfgenerated auxiliary motor 33B reduces the total current flow to the twomotors. Therefore, the load of auxiliary motor 33B is, to a first-orderapproximation, non-dissipative.

During accessing and start-up, a high torque and speed are desired tominimize delay in reaching selected and steady operation. Therefore,during start-up and accessing, main motor 33A and auxiliary motor 33Bare supplied with equal drive voltages thereby driving disk D with twicethe drive torque of playback operation, causing turntable 102 to reachplayback speed quickly. Thus, optical pickup 2 can begin reading disk Dquickly, and the access time can be shortened. Since main motor 33A andauxiliary motor 33B are powered equally, vibration due to backlashbetween connected gears 35-37 is transmitted to turntable 102. However,this vibration presents no problem since the vibration is onlyundesirable during playback, not during acceleration or deceleration ofdisk D. Background information relating to the motor drive circuit canbe found in Japanese Patent Application Serial Number 6-340510 (filedDec. 28, 1994).

A centering cone 101, projecting from the top surface of turntable 102,precisely centers disk D with respect to turntable 102. A magnet 105,inside centering cone 101, attracts a clamper 1009 (not shown in FIG. 9and described below). Guide rods 31, 38, mounted in chassis 30, guideoptical pickup 2 along a linear scanning path that forms an angle of 25degrees in the clockwise direction with the front side of main chassis90. The scanning path of optical pickup 2 is a radial line of disk Dwhen disk D is mounted on turntable 102. A scanning motor 34 and opticalpickup transfer mechanism 53, that includes deceleration gears 51, 52,54, and a rack 50, enable a scanning movement of optical pickup 2.Optical sensors 230A, 230B detect the rotation of a shutter wheel 55,driven by a gear 51. This allows the distance of scanning movement to bedetected.

Lower clampers 41, fitted into attachment holes 30S on chassis 30,vibrationally isolate chassis 30 with optical mechanism 1006, from abase 40. A respective spring 42, between each lower clamper 41 and base40, supports the weight of chassis 30. Fasteners 43 insert through upperclampers 44 on the upper surface of clamper 41 passing through lowerclampers 41 to connect to base 40.

A clamper lock mechanism 1007, selectively locks optical mechanism 1006on chassis 30 to a base 40 from which optical mechanism 1006 isotherwise vibrationally isolated. Damper lock mechanism 1007 includes aY-shaped lock plate 64 with pins 64C projecting from its lower surface.Pins 64C fit into guide grooves 40D on base 40, permitting lock plate 64to move over a limited range and direction defined by guide grooves 40D.A J-shaped lock plate 65 also has a pin 65B, projecting from its lowersurface, that fits into a guide groove 40E on base 40, permitting lockplate 65 to move along a limited path defined by guide groove 40E.Engagement tips 64A and 64B of lock plate 64 pass through holes 40A and40B, located on a right side of base 40, and insert into holes 30A and30B, respectively, located on a right side of chassis 30. Engagement tip65A of lock plate 65 passes through a hole 40C located on a left side ofbase 40, and inserts into hole 30C (as visible in FIG. 9), which issimilar to holes 30A and 30B, located on a left side of chassis 30. Lockplates 64 and 65 are interconnected by connecting plate 66, whichrotates on a shaft 67 projecting upwardly from base 40. A compressionspring 68 is inserted between base 40 and lock plate 64, urging lockplate 64 toward the right side of base 40. Thus, lock plates 64 and 65move in opposite directions against, and with, the force of compressionspring 68. A notch 66A on an end of connecting plate 66 passes though anopening 40F in base 40. A sliding plate 75 (described later) engagesnotch 66A to control the angular position of connecting plate 66.

As visible in FIG. 9, holes 30A-30C are have curved upper and loweredges. Also apparent from FIG. 9 is that engagement tips 64A, 64B and65A are pointed with a portion at the base of each point that is largerthan holes 30A-30C. If, when engagement tips 64A, 64B, and 65A of lockplate 64 and lock plate 65 pass through holes 40A, 40B, and 40C andinsert into holes 30A, 30B, and 30C engagement tips 64A, 64B, and 65Aare positioned slightly out of alignment with holes 30A-30C, the shapeof holes 30A-30C will tend to force engagement tips 64A, 64B, 65A to thecenter. In addition, by arranging for an upper horizontal edge of eachhole 40A, 40B, 40C to be vertically aligned with respect to a respectiveone of engagement tips 64A, 64B, and 65A and a respective one of holes30A, 30B, and 30C such that the flat of the base of each of engagementtips 64A, 64B, and 65A is pressed against the horizontal edge of therespective one of each hole 40A, 40B, and 40C base 40 is also firmlyaligned with respect to chassis 30. Not only does this arrangementsecure a positive vertical position of the tips with respect to chassis30, because of the curved shape of the edge of the corresponding one ofholes 30A-30C, each tip is also horizontally aligned within thecorresponding one of holes 30A-30C. The horizontal alignment ofengagement tips 64A, 64B, and 65A serves to horizontally align chassis30 and base 40 because the horizontal width of holes 40A, 40B, 40C isnearly the same as the width of the base of the respective one ofengagement tips 64A, 64B, and 65A which insures they are preciselyaligned in the holes 40A, 40B, 40C.

Referring now to FIGS. 30-33 and 66, clamper lock mechanism 1007 islocked and unlocked in response to the position of sliding plate 75. Anedge 75B" of sliding plate 75 is at a substantial distance from a notch66A of connecting plate 66 when sliding plate 75 is between positionDOWN-2 and position UP-1. Thus, while sliding plate 75 is betweenposition DOWN-2 and UP-1, lock plates 64 and 65 are urged toward theright side of housing 1000 by the force of compression spring 68 forcingengagement tips 64A, 64B, and 65A into holes 30A-30C of chassis 30. Thiscauses optical mechanism 1006, on chassis 30, to be locked to base 40.When sliding plate 75 is moved from position UP-1 to position UP-2, edge75B" engages notch 66A turning connecting plate 66 counterclockwiseagainst the force of compression spring 68. Lock plate 64 is therebymoved toward the left side of housing 1000, and lock plate 65 toward theright side of housing 1000, causing engagement tips 64A, 64B, and 65A todisengage from holes 40A-40C of base 40 and holes 30A-30C of chassis 30,respectively. Thus freed, in position UP-2, optical mechanism 1006 iselastically supported by lower clampers 41 and upper clampers 44.

Referring to FIGS. 10, 45, and 47, a vertical transport mechanism 1008,raises and lowers base 40, with the attached optical mechanism 1006,between an up position (FIG. 47) and a down position (FIG. 45). In theup position, disk D is played back. In the down position, opticalmechanism 1006 is shifted down and away from disk D to clear the way fortransfer of disk D.

Vertical transport mechanism 1008 raises and lowers base 40, which issupported at its forward side on guide pins 45A and 45B and at its rearend on ramp channel 48'. Ramp channel 48' is cut out of a stainlesssteel guide plate attached to base 40 at the rear end thereof. Guidepins 45A and 45B rest in ramp channels 75A' and 75B' in bends 75A and75B, respectively, of sliding plate 75. Ramp channel 48' rests on pin47, inserted in an opening in a vertical extension 75C in sliding plate75. Base 40, with elastically supported optical mechanism 1006, rides upand down on guide shafts 137A, 137B, which are attached to main chassis90 and passing through openings in base 40. Sliding plate 75 istranslated left and right relative to main chassis 90 causing guide pins45A and 45B to ride up and down in ramp channels 75A' and 75B',respectively, and simultaneously causing ramp channel 48' to rideupwardly on pin 47.

Shafts 136A-136C, screwed into main chassis 90, guide the left and rightmovement of sliding plate 75. Shafts 136A-136C pass through channels 75Hin sliding plate 75. Shafts 136A-136C have wide heads to hold slidingplate 75 adjacent to main chassis 90. A worm gear 254 pressed onto arotating shaft 251A of a motor 251 meshes with a gear 184A of a gearmember 184, which rotates on shaft 92 projecting upwardly from mainchassis 90. Another gear 184B of gear member 184 meshes with a gear 71,which in turn meshes with a gear 72. Gear 72 in turn meshes with a largediameter gear of gear element 73. A small diameter gear of gear element73 meshes with a large diameter gear of gear element 74. A smalldiameter gear 74A of gear element 74 in turn meshes with an integralrack 75F in sliding plate 75. Gears 71 and 72, and gear elements 73 and74, all rotate on respective integral shafts that fit into respectiveholes in the bottom of main chassis 90. Therefore, rotation of motor 251translates sliding plate 75 left and right.

A shutter wheel 58, attached to a top of gear member 184, periodicallyinterrupts a light beam of an optical sensor 233, supported on a bracket181, as gear member 184 rotates, to generate a series of signals(sliding plate motion pulse signal, P .PULSE, described below). Thisseries of signals is used by a controller to determine the position ofsliding plate 75.

Referring now also to FIG. 66, horizontal portions G1 of ramp channels75A' and 75B' guide pins 45A and 45B of base 40, without lifting them,as sliding plate 75 moves between a position DOWN-2 (shown in FIGS. 34and 35) and a position DOWN-1 (shown in FIGS. 36 and 37). Thus, base 40,with optical mechanism 1006, remains in the down position (opticalmechanism 1006 is shown in the down position in FIG. 45), below disk Din the playback position. When sliding plate 75 moves between positionDOWN-1 and position UP-1 (the latter shown in FIGS. 38 and 39), guidepins 45A and 45B are lifted by sloping portions G2 of ramp channels 75A'and 75B', thereby lifting optical mechanism 1006. When sliding plate 75moves between position UP-1 and position UP-2 (the latter shown in FIGS.40 and 41), guides pins 45A and 45B remain in horizontal portions G3 andoptical mechanism remains in the up position (optical mechanism 1006 isshown in the up position in FIG. 47) for disk playback. In the upposition, optical mechanism 1006 is at the level of a lower surface ofdisk D, d in the playback position and mounted on the upper surface ofturntable 102. Therefore, there is no need to displace disk D, d, as ina tray-type disk player, to play disk D, d back. As can be seen frominspection, guide groove 48' and pin 47 cooperate in such a way that therear end of base 40 is lifted in concert with the forward end, just asdescribed above.

One pulse of signal P. PULSE indicates approximately 0.231 mm ofmovement of sliding plate 75. A shutter piece 75G, on a bend on slidingplate 75, interrupts a light beam generated and sensed by optical sensor237 on main chassis 90. Thus, optical sensor 237 detects a referenceposition of sliding plate 75 at the point where shutter piece 75G justceases to interrupt the light beam as sliding plate 75 moves to theright of position DOWN-1 or just interrupts as sliding plate 75 movesleft of position UP-1. This reference signal, generated by opticalsensor 237, is signal P. REF. Signal P. REF goes low (L) when shutterpiece 75G ceases to interrupt the light beam generated by optical sensor237 and goes high when the beam is interrupted.

The positions of sliding plate 75 are determined by counting the numberof pulses of signal P. PULSE after the signal P. REF goes low (L).Position DOWN-1 is detected by moving sliding plate 75 leftwardly aftersignal P. REF goes high (H), and halting after counting three pulsesfrom signal P. PULSE. Sliding plate 75 is positioned at position DOWN-2by halting after counting 20 pulses. Sliding plate 75 is positioned atposition UP-1 by moving sliding plate 75 to the right until signal P.REF goes low (L) and stopping after counting 27 pulses of signal P.PULSE. Sliding plate 75 is positioned at position UP-2 by halting arightward movement after counting 45 pulses.

Referring to FIGS. 2 and 49, a clamper 1009 clamps disk D on turntable102. Clamper 1009 includes a clamper base 100 with a bottom surface towhich a ferromagnetic plate 111, is attached. A clamp support 115 has aflange 115A top and a shaft 115B which passes through an opening 80G inloading chassis 80. Flange 115A tapers at its perimeter. Shaft 115B isinsertably fixed to clamper base 100. A clamping sheet of compressedurethane is adhesively bonded to the outer perimeter of the bottomsurface of clamper base 100 to protect disk surfaces from damage.Turntable 102 has a magnet 105 which is positioned to attractferromagnetic plate 111.

Referring also to FIGS. 43 and 47, a clamper support mechanism 1010holds clamper 1009 slightly (0.3 mm) above disk D when disk D is in theplayback position. Respective pins 78, 78, projecting upwardly from theupper surface of loading plates 81L and 81R, pass through guide groove80D of loading chassis 80 and insert into guide grooves 77B and 77B ofclamper holder 77L, 77R. Respective projections 77C, 77C, projectingdownwardly from clamper holders 77L, 77R, pass through, and are guidedby, respective guide grooves 80E, 80E of loading chassis 80. Thus,clamper holders 77L, 77R are free to move left and right with respect toloading chassis 80. Clamper holders 77L, 77R have respective supports77A, 77A on respective ends which face each other. Supports 77A, 77A areshaped to clamp and support flange 115A of clamper 1009 when supports77A, 77A are brought together. Support 77A has a V-shaped cross section.A spring 128 urges clamper holders 77L and 77R together to snuglyembrace flange 115A. Flange 115A fits precisely in supports 77A, 77A ina definite position when supports 77A, 77A are brought together. Thus,supports 77A, 77A hold flange 115A at a precise vertical positionkeeping clamper 1009 at 0.3 mm above disk D.

Referring to FIGS. 42-45, clamper support mechanism 1010 supportsclamper 1009 above disk D responsively to movement of loading plates 81Land 81R as follows. When loading plates 81L and 81R are moved between adisk receiving position (POS. 1, shown in FIGS. 42 and 43) andlarge-diameter disk support position (POS.3 shown in FIGS. 44 and 45),pins 78, 78, on loading plates 81L and 81R, travel in guide grooves 77B,77B of clamper holders 77L, 77R without affecting clamper holders 77Land 77R. The force of spring 128 brings clamper holders 77L, 77Rtogether causing supports 77A, 77A to hold clamper 1009 0.3 mm abovedisk D in the playback position.

Referring now also to FIGS. 46-49, optical mechanism 1006 is raised tothe up position. Next, loading plates 81L and 81R are separated (an openposition, POS.4 shown in FIGS. 48 and 49). In the open position,respective pins 78, 78 on loading plates 81L and 81R press againstrespective ends of guide grooves 77B, 77B spreading clamper holders 77Land 77R apart against the force of spring 128. This causes supports 77A,77A to release flange 115A. Clamper 1009 is then attracted to magnet 105of turntable 102 clamping disk D between turntable 102 and clamper 1009.Loading plates 81L and 81R are brought to the open position (POS.4) evenafter disk D has been moved to the stock position so that the stockercan be moved up and down. When this happens, since no disk D is presenton turntable 102 in the up position, clamper 1009 is attracted to magnet105, and rests on centering cone 101 of turntable 102, as shown in FIG.50.

Referring to FIGS. 2 and 50, a shutter piece 77L' on clamper holder 77Lindicates clamp errors the outer perimeter position of loading plates81L and 81R. An optical sensor 234, on loading chassis 80, detects theposition of shutter piece 77L'. Optical sensor 234 generates a loadingplate outermost position detection signal (OUT) which is at a high levelH when supports 77A, 77A are tightly held together around flange 115Aand at a low level (L) when supports 77A, 77A are moved apart.

Referring now to FIG. 51, supports 77A, 77A have wedge-shaped crosssections. If flange 115A is forced upwardly or downwardly, supports 77A,77A can be spread apart. This may happen if, when optical mechanism 1006is moved to the up position, disk D is misaligned with respect toturntable 102. Turntable 102 will force disk D upwardly against clamper1009 causing supports 77A, 77A to spread apart. This will cause the OUTsignal to go low indicating an error condition. Note that, in the upposition of optical mechanism 1006, the upper surface of turntable 102and the lower surface of disk D precisely coincide. Therefore, normally,the movement of turntable 102 to the up position should not raise disk Dat all. Note also that as clamper 1009 is attracted toward turntable 102due to the magnetic force of magnet 105, and since there is only 0.3 mmof clearance above disk D, clamper holders 77L, 77R are not forcedsubstantially apart even if clamper 1009 is lowered to the surface ofdisk D. Therefore, unless loading plates 81L and 81R have been broughtto the open position POS.4, the output from optical sensor 234 shouldremain in the high (H) state even when optical mechanism 1006 has movedto the up position. Thus, the output from optical sensor 234 (signalOUT) is also used to detect clamping errors between clamper 1009 andturntable 102.

Referring now to FIG. 65, signal OUT goes low (L) when loading plates81L and 81R separate beyond the point where a large-diameter disk can besupported between timing belt 14 and friction belt 12 at position POS.3.This serves as a reference point for the determination of otherpositions of loading plates 81L and 81R. Moving laterally from thisreference position, where signal OUT goes low, and counting 11 pulses ofsignal L. PULSE, position POS.4 is identified. Positions POS.1-POS.3 arerepresented, respectively, by 13, 76, 83 pulses of signal L. PULSE asloading plates 81L and 81R travel medially from position POS.4.

Referring to FIG. 11, a stocker 1011 is generally defined by a top plate151, a base plate 154, and a stocker body 150. Stocker plates 152A-152Dare insertably affixed in respective slits of stocker body 150. Sheets153, of the non-woven cloth, the same used as a case lining to protectfloppy disks, are adhesively bonded to top and bottom surfaces ofstocker plates 152A-152D and top plate 151. Sheets 153 are folded andwrapped around forward ends of stocker plates 152A-152D and top plate151. Stocker 1011 removably supports a total of four disks (not shown inthe drawing) at a pitch of 3 mm between top plate 151 and stocker plate152D. A first stored disk is inserted between top plate 151 and stockerplate 152A. A second stored disk is stored between stocker plates 152Aand 152B. A third stored disk is stored between stocker plates 152B and152C. A fourth stored disk is stored between stocker plates 152C and152D. Sheets 153 provide cushioning and low frictional drag, and therebyserve to protect disks D, d during insertion into the spaces betweenstocker plates 152A-D. The spacing between adjacent ones of stockerplates 152A-152D is substantially the same size as the thickness of diskD, d. In addition, each of stocker plates 152A-D has a width,perpendicular to the path of insertion disk d follows moving into andout of stocker 1011, that is smaller than the diameter of disk d. Thisinsures that timing belt 14 and friction belt 12 can engage oppositeedges of disk d at all times moving into and out of the stocker 1011.

A shaft 140, projecting upwardly from main chassis 90, is inserted in abearing 150A to guide stocker 1011 along a vertical path of movement.Nuts 164L, 164R (nut 164L is hidden in the drawing) engage screws 167L,167R that rotate on shafts 165L, 165R, respectively, projecting upwardlyfrom main chassis 90. Thus, rotation of screws 167L, 167R moves stocker1011 vertically. A stocker vertical transfer mechanism 1012, locatedbelow stocker 1011, drives screws 167R, 167L. A motor 252, supported bybracket 182 on main chassis 90, has a rotating shaft with a press-fittedworm gear 62. A gear member 169, rotatably supported by shaft 170, has agear 169A, on an upper portion thereof, that meshes with worm gear 62. Agear 169B on a lower portion of gear member 169 meshes with a gear 167Aattached to screw 167L. Gear 167A meshes with a gear 168L. Gear 168Lmeshes with a gear 166 which in turn meshes with a gear 168R. Gear 168Rmeshes with a gear 167A attached to screw 167R. Clockwise rotation ofscrews 167R and 167L lowers stocker 1011, and counterclockwise rotationof screws 167R and 167L raises stocker 1011.

A shutter member 173 rotates on a shaft projecting upwardly from mainchassis 90. Shutter member 173 has a gear 173A, on its lower surface,that meshes with a gear 168A coaxially connected to gear 169L. Rotationof shutter member 173 is detected by optical sensors 238 and 239 andused to determine the vertical movement and position of stocker 1011. Ashutter piece 173B projects from an edge of shutter member 173 and slitsS1-S4 in shutter member 173 divide shutter member 173 at 90 degreeintervals. Shutter piece 173B and slits S1-S4 are detected by opticalsensors 238 and 239, respectively, on a disk lock base 155.

Optical sensor 238 generates a stocker reference position signal (S.REF), when shutter piece 173B interrupts a light beam generated anddetected by optical sensor 238. Signal S. REF goes high when stocker1011 is brought to a position above disk holding position POS(1). POS(1)of stocker 1011 corresponds to an alignment of the disk-holding spacebetween top plate 151 and stocker plate 152A with a disk transferposition.

Optical sensor 239 generates a stocker position signal (S. POS). Eachtime stocker 1011 passes one of positions POS(1)-POS(4), the signal goeslow (L). Thus, position POS(1) is detected by moving the stockerdownward until signal S. POS goes low (L) after signal S. REF goes high(H). The remaining positions POS(2), POS(3), and POS(4) are detectedmoving stocker 1011 further and counting second, third, or fourthchanges in signal S. POS, respectively.

Referring to FIGS. 12, 53, and 55, a disk lock mechanism 1013, preventsdisks, held in stocker 1011, from moving out of stocker 1011. An upperdisk lock shaft 158 projects downwardly from a lower surface of topcover 3. Upper disk lock shaft 158 passes through spindle holes of disksstored in stocker 1011. A lower end of upper disk lock shaft 158 extendsto a position slightly (0.8 mm) above an upper surface of a disk D beingtransported into stocker 1011 as shown in FIG. 55. Upper disk lock shaft158 prevents movement of the disks above the disk D being transported.FIGS. 53 and 55 show the stocker in position POS(1), so upper disk lockshaft 158 does not pass through any of the disk spindle holes withinstocker 1011. A lower disk lock shaft 156 projecting upward from mainchassis 90 is coaxially aligned with upper disk lock shaft 158.

Lower disk lock shaft 156 rides on a shaft 155A of disk lock base 155permitting lower disk lock shaft 156 to move vertically. Lower disk lockshaft 156 moves between a lock position and an unlock position. In thelock position, a tapered upper end of lower disk lock shaft 156 fitsinto upper disk lock shaft 158 (see FIG. 53). In the unlock position,lower disk lock shaft 156 is lowered away from upper disk lock shaft158, creating a gap between upper and lower disk lock shafts 158 and 156through which a disk can pass (see FIG. 55). A spring 159 inside lockshaft 156 applies an upward force on lower disk lock shaft 156. A sheet157, of compressed urethane, is attached to the upper surface of lowerdisk lock shaft 156 to help avoid possible disk damage.

To raise and lower lower disk lock shaft 156, disk lock mechanism 1013includes a lock release arm 172 rotatably supported by a shaft 183 ofdisk lock base 155. Lock release arm 172 has a pressing portion 172Athat engages upper surfaces of projections 156A at a base of lower disklock shaft 156. Spring 178 applies a clockwise rotating force to lockrelease arm 172 sufficient to overcome the force of spring 159 therebyforcing lower disk lock shaft 156 to its lowermost position. A relayplate 96 moves toward the front and rear guided by integral guidegrooves 96C, 96C that engage pins 97 on main chassis 90. A rear-facingsurface 96A of relay plate 96 pushes against an engagement portion 172Bof lock release arm 172 to rotate lock release arm 172 counterclockwiseagainst the force of spring 178. An engagement portion 96B on a lowersurface of relay plate 96 engages with a cam surface 75D, havingsurfaces C1-C5, on an edge of sliding plate 75 (visible in FIGS. 52, 54,56, and 58).

Referring now to FIGS. 12 and 52-59, lower disk lock shaft 156 ispositioned responsively to the position of sliding plate 75. Whensliding plate 75 is in a position DOWN-2, engagement portion 96B ofrelay plate 96 is engaged with surface C1 of cam surface 75D. Inposition DOWN-2, as shown in FIG. 53, lock release arm 172 is rotated toa position in which it exerts no downward force on lower disk lock shaft156. Thus, in position DOWN-2, lower disk lock shaft 156 is seated inupper disk lock shaft 158, the lock position, held there by the force ofspring 159.

When sliding plate 75 moves toward the right side of housing 1000(toward the up position of optical mechanism 1006), engagement portion96B of relay plate 96 follows sloped surface C2 of cam surface 75D,moving relay plate 96 toward the front of main chassis 90. As engagementportion 96B follows sloped surface C2, lock release arm 172 rotatesclockwise under the urging of spring 178, forcing lower disk lock shaft156 gradually downward. When sliding plate 75 reaches a position DOWN-1,shown in FIG. 54, engagement portion 96B of relay plate 96 rests onsurface C3. Lock release arm 172 halts at the angle shown in FIG. 55,and lower disk lock shaft 156 is held at the unlock position, permittingdisk transfer.

As sliding plate 75 is translated further to the right side of housing1000, engagement portion 96B of relay plate 96 is pushed rearward byinclined surface C4. Lock release arm 172 rotates counterclockwise, andlower disk lock shaft 156 begins moving upwardly under the urging ofspring 159. When sliding plate 75 reaches a position UP-1, shown in FIG.56, engagement portion 96B is held by the approximately central area ofsloped surface C4, in which lower disk lock shaft 156 moves upward tothe position indicated in FIG. 57. When sliding plate 75 reaches aposition UP-2, engagement portion 96B engages with surface C5, which isaligned with surface C1. At this point, as shown in FIG. 58, lower disklock shaft 156 has reached the lock position again, where it fits intoupper disk lock shaft 158.

A shutter 156B, projecting from lower disk lock shaft 156, indicateswhen lower disk lock shaft 156 reaches the lock position. Shutter 156Binterrupts a light beam generated and detected by an optical sensor 229,attached to disk lock base 155 when lower disk lock shaft 156 is at theunlock position. Optical sensor 229 generates a disk lock signal (D.LOCK), which is high when lower disk lock shaft 156 in the unlockposition. When sliding plate 75 is at position UP-2 or position DOWN-2,lower disk lock shaft 156 is at the lock position, as described above.However, if disk D is not positioned with its center hole aligned withlower disk lock shaft 156, lower disk lock shaft 156 is blocked by diskD, preventing it from reaching the lock position. If disk locking is notproperly achieved, vibrations can cause disks to shift out of placewithin stocker 1011, possibly causing damage to the disks by lower andupper disk lock shafts 156 and 158 which move vertically within stocker1011. Signal D. LOCK is used to detect such disk-locking errors.

Referring to FIGS. 60-64, a disk insertion error preventing mechanism1014 prevents errors during insertion of disk D. A shutter 120 rotateson a shaft 129 rotatably supported at either end by bends 80F, 80Fprojecting from loading chassis 80. Flaps 120A, 120A, projectingradially from an axis of rotation of shutter 120, block insertionaperture 1A on front panel 1. A pinion gear 120B, subtends a 180 degreearc about the axis of rotation of shutter 120. Material, such as felt orcompressed urethane, is adhesively bonded to the surface of flaps 120A,120A to prevent abrasion of the top surface of disk D, since the topsurface of disk D engages flaps 120A during loading and ejectingoperations.

A shutter arm 121 rotates on a shaft 122 projecting perpendicularly fromthe lower surface of loading chassis 80. A spring 125 urges shutter arm121 in a counterclockwise direction, as viewed from the top. A rack 121Aon the bottom of shutter arm 121 meshes with pinion gear 120B. Thus,shutter 120 opens and closes responsively to the rotation of shutter arm121. A pin 123, fixed on the upper surface of the loading plate 81L,engages with side surface 121B of shutter arm 121 responsively tomovement of plate 81L.

Referring now also to FIG. 65, the angle of shutter 120 changesresponsively to the position of loading plate 81L. Referring to FIG. 60,when loading plates 81L and 81R are positioned at disk receivingposition POS. 1, pin 123 of loading plate 81L rotates shutter arm 121clockwise against the urging of spring 125. The rotation of shutter arm121 causes shutter 120 to rotate toward the outside of the device,moving it to the open position. This allows a disk to be inserted intoinsertion aperture 1A.

The insertion of disk D causes loading plates 81L and 81R to separate.As loading plate 81L moves to the left side of housing 1000, pin 123moves away from shutter arm 121 permitting spring 125 to rotate shutterarm 121 counterclockwise. As shutter arm 121 rotates, flaps 120A movedownwardly until they rest on the top surface of disk D, as shown inFIG. 64. Pin 123 continues to move away from side surface 121B ofshutter arm 121. Once disk D is driven by disk transfer mechanism 1001completely inside the disk player, flap 120A is released to a closeposition in which shutter arm 121 is rotated counterclockwise to aposition where its side surface 121B engages with bend 80F of loadingchassis 80. When shutter 120 is in the close position, disk insertionthrough insertion aperture 1A is prevented. Shutter 120 cannot rotatepast the close position in which flaps 120A point downwardly because anarm supporting rack 121A is supported by bend 80F, preventing furtherrotation of shutter 120. Thus, insertion of another disk is blocked.

A shutter piece 120C, on the upper part of shutter 120, interrupts alight beam generated by an optical sensor 235, on loading chassis 80, todetect the closure of shutter 120. The closure of shutter 120 isindicated by shutter close signal (S.CLOSE) generated by optical sensor235. Signal S.CLOSE goes high when shutter 120 closes.

Referring now also to FIGS. 7, 16, and 21 the change in signal S.CLOSEto high (H) serves as a reference position for disk transport within thedisk player. The disk transfer position is determined by counting thenumber of pulses from the output (signal L. PULSE) of optical sensor 232described above. When a large diameter disk D is inserted andtransported to position P1, flap 120A falls away from the upper surfaceof disk D, closing shutter 120. This causes signal S.CLOSE to go high.Play position P2 and stock position P3 are determined for a largediameter disk D by counting pulses from signal L. PULSE. For playposition P2, six pulses are counted. For stock position P3, 160 pulsesare counted. For a small-diameter disk d, play position P2 is indicatedby 46 pulses of signal L. PULSE and stock position P3 by 200 pulses ofthe same signal.

Referring to FIG. 67, a drive control circuit 1015 includes a systemcontroller 300 (preferably a microprocessor) having a ROM, a RAM, and aninterface circuit. Controller 300 receives user input from a mode keypad301, with E/L key 1-E/L key 4, which a user presses to commandcontroller 300 to eject and load disks stored in positions 1-4 ofstocker 1011, respectively. Controller 300 is also connected to acomputer 303 via an interface circuit 302. Controller 300 implementsmechanism operations corresponding to mode key entries and commands fromcomputer 303 according programming described in the flowcharts of FIGS.68-81.

Optical sensors 232, 235, 234, and 236 apply signals L. PULSE, S. CLOSE,OUT, and IN, respectively, to controller 300. Controller 300 generatesand applies signals FRONT and REAR to motor drive circuit 304, tocontrol cause drive motor to move the disk toward the front and rear,respectively, and to cause drive motor 250 to open and close loadingplates 81L and 81R, respectively. Motor drive circuit 304 applies adrive voltage to drive motor 250. When signal FRONT goes high (H), adrive voltage is applied by motor drive circuit 304 to rotate timingpulley 15 counterclockwise. When signal REAR goes high (H), a drivevoltage is applied to by motor drive circuit 304 to rotate timing pulley15 in the counterclockwise direction. When both signals go high (H), theoutput from motor drive circuit 304 is short-circuited toelectromagnetically brake motor 250. When both signals are low (L), theoutput of the motor drive circuit is an open lead state to allow themotor 250 to freewheel.

Optical sensors 237 and 233 apply signals P. REF and P. PULSE,respectively, to controller 300. In response to signals P. REF and P.PULSE, controller 300 generates and applies signals P.UP and P.DWN tomotor drive circuit 305, to control the position of sliding plate 75.Motor drive circuit 305 outputs a predetermined drive voltage to motor251 of optical mechanism vertical transport mechanism 1008 of FIG. 10.When signal P.UP goes high (H), a drive voltage is output to movesliding panel 75 toward the right side of housing 1000. When signalP.DWN goes high (H), a drive voltage is output to move sliding panel 75toward the left side of housing 1000. When both signals P.UP and P.DWNgo high (H), motor drive circuit 305 is short-circuitedelectromagnetically brake motor 251. When both signals are low (L), theoutputs are put in an open lead state to allow motor 251 to freewheel.

Optical sensors 238, 239, and 229 apply signals S. REF, S. POS, and D.LOCK, respectively, to controller 300. In response to these signals,controller 300 generates and applies signals ST.UP and ST.DOWN to motordrive circuit 306, which drives motor 252 of stocker vertical transfermechanism 1012. When signal ST.UP goes high (H), a drive voltage isoutput to move stocker 1011 upward. When signal ST.DOWN goes high (H), adrive voltage is output to move the stocker downward. When both signalsare high (H), the output from motor drive circuit 306 isshort-circuited, electromagnetically braking motor 252. When bothsignals are low (L), the motor leads are opened to permit motor 252 tofreewheel. When a power supply is off, controller 300 is connected to abackup power supply (not shown in the drawing) so that flags in memoryindicating stocker position, presence of disks and disk sizes are saved.

The read signal generated by optical pickup 2 is applied to a signalprocessing circuit 307 via an RF amp 309. After EFM demodulation,de-interleaving, error correction and other usual operations areperformed, the signal is sent to computer 303, which is connectedexternally, via an interface circuit 302. Based on a servo error signal,obtained from optical pickup 2, servo circuit 308 controls a focusservo, tracking servo, and feed servo of optical pickup 2. This controlcauses a light beam, generated by optical pickup 2, to follow datatracks on disk D. Signal processing circuit 307 and servo circuit 308are connected to controller 300, and control operations are performedbased on the operating mode.

Referring to FIGS. 68-81, the letter, n, denotes the stocker position(i.e. n=1, 2, 3, or 4). Four flags, D.FLAG(n) (D.FLAG(1)-D.FLAG(4)), onefor each stocker position, indicate the presence of disks in respectiveones of the holding positions POS(1)-POS(4) of the stocker. Four otherflags, S.FLAG(n) (S.FLAG(1)-S.FLAG(4)), indicate the sizes of the diskstored in the respective ones of the holding positions POS(1)-POS(4). Avalue of 1 of one of flags D.FLAG(n) means a disk occupies therespective holding position POS(n). A value of 1 of one of flagsS.FLAG(n) means a disk in POS(n) is a small-diameter disk. For example,if D.FLAG(1) and S.FLAG(1) are both set to 1, then a small-diameter diskis stored in holding position POS(1) of the stocker, the topmost level.M.FLAG indicates the operating mode of the device.

A flag M.FLAG is set to READY when in the disk player is in the diskreceiving state shown in FIG. 13. When a disk D (or d) is brought to theeject position, as shown in FIGS. 19 and 24, M.FLAG is set to EJECT.When disk D, d is clamped and loading plates 81L and 81R are brought tothe open position, as shown in FIGS. 17 and 22, M.FLAG is set toSTAND-BY. When the disk is brought to stock position and loading plates81L and 81R are brought to open position, as shown in FIGS. 18 and 23,M.FLAG is set to STOCK. In the stand-by state, M.FLAG is set to PLAYwhen disk playback is commenced.

The disk player can be in any of a number of different operating modesto which the control program is responsive. These modes are indicated bycorresponding settings of M.FLAG. The following table summarizes thesemodes. The modes shown for each mechanism are not necessarilycomprehensive but are those used to characterize the operating modessignalled by M.FLAG.

    ______________________________________    State  Description    ______________________________________    Disk Transfer Mechanism 1001    Receive           Disk receiving state with loading plates 81L and 81R in disk           receiving position POS. 1 shown in FIG. 13.    Eject  Disk transfer mechanism 1001 supports disk D, d between           timing belt 14 and friction belt 12 with the disk at the eject           position, where it can be removed as shown in FIGS. 19 and           24.    Open   Disk transfer mechanism 1001 is in the open position,           POS. 4, where timing belt 14 and friction belt 12 are           separated from the outer perimeter of disk D, d as shown in           FIGS. 17 and 22.    Loading Plate Opening and Closing Mechanism 1094    On     Rack member 87 is engaged with timing pulley 15 keeping           disk transfer mechanism 1001 in the open position POS. 4 as           shown in FIG. 29.    Off    Rack member 87 is moved away from timing pulley 15 as           shown in FIG. 25.    Damper Lock Mechanism 1007    Locked Optical mechanism 1006 is locked to base 40 a shown in FIG.           30.    Unlocked           Optical mechanism 1006 is unlocked from base 40 and           elastically supported by lower dampers 41 and upper dampers           44 as shown in FIG. 33.    Sliding Plate 75 Position    DOWN-2 Optical mechanism vertical transport mechanism 1008 has           lowered optical mechanism 1006 to the down position as           shown in FIG. 43.    UP-2   Optical mechanism vertical transport mechanism 1008 moves           raised optical mechanism 1006 to the up position as shown in           FIG. 49.    Clamper Support Mechanism 1010    Release           Support released on clamper 1009 and clamper 1009 is           attracted to magnet 105 of turntable 102 as shown in FIG. 50.    Support           Clamper 1009 is supported at the support position shown in           FIGS. 42 and 43.    Disk Lock Mechanism 1013    Locked Lower disk lock shaft 156 is in a lock position as shown in           FIGS. 52 and 53.    Disk Insertion Error Prevention Mechanism 1014    Engaged           Positioning of flap 120A is maintained at the angle at which           flap 120A of shutter 120 engages with the top surface of disk           D as shown in FIG. 64.    Closed Shutter 120 is in a fully closed position preventing the           insertion of a disk into insertion aperture 1A (see FIG. 63).    Open   Shutter 120 is in the open position, allowing a disk to be           inserted into insertion aperture 1A as shown in FIGS. 60 and           61.    ______________________________________    Mechanism States in Modes Indicated by M. FLAG    Operating Modes - M. FLAG    Mechanism            READY    EJECT     PLAY/STANDBY                                          STOCK    ______________________________________    1001    Receive  Eject     Open       Open    1004    Off      Off       On         On    1007    Lock     Lock      Unlock     Unlock    75      DOWN-2   DOWN-2    UP-2       UP-2    1010    Support  Support   Release    Release    1013    Lock     Lock      Lock       Lock    1014    Open     Open      Closed     Closed    ______________________________________

When the power supply is turned on, controller 300 begins executing amain routine that loops through steps S1, S3, S5-10 unless an event, asdescribed below, is detected.

When disk D is inserted into insertion aperture 1A of front panel 1, theouter edge of disk D presses against timing belt 14 and a disk guide11E. As the disk is pushed in by the user, the outer edge of the diskslides against disk guide 11E, loading plates 81L and 81R are forcedapart, and pin 123, on loading plate 81L, moves allowing spring 125 torotate shutter arm 121 counterclockwise. The rotation of shutter arm 121closes shutter 120. Shutter 120 is held open as it slides against disk Duntil disk D is inserted completely into the device. The disk isprotected from damage by the compressed urethane or similar material)adhesively bonded to the periphery of flap 120A.

If a disk is inserted as far as position P0 (shown in FIG. 14 for alarge disk and in FIG. 20 for small-diameter disks), the output ofoptical sensor 236 (signal IN) goes high (H) causing the control programto branch from step S1 to step S2 and then to a procedure JOB LOAD. Inprocedure JOB LOAD, disk D, d is brought to the playback position insteps S20-S34 as follows. First, controller 300 outputs a high (H) stateat signal REAR at step S20. Control then loops at step S21 till signalS.CLOSE goes high (H), indicating shutter 120 has closed. The high level(H) output by signal REAR causes timing belt 14 to be rotatedcounterclockwise, rolling disk D, d clockwise along the left sidesurface of friction belt 12, and toward the rear of housing 1000.

Once the disk reaches position P1 (FIG. 16 for large disks or positionP6 in FIG. 21 for small-diameter disks), flap 120A of shutter 120 dropsfrom the upper surface of disk D, d to the closed position. This causesthe output from optical sensor 235, signal S.CLOSE, to go high (H).Controller then checks signal IN at step S22. If signal IN is high (H)at step S22, indicating a small diameter disk, controller 300 setssmall-diameter disk flag S.FLAG(n) to 1 at step S23, where n is aninternal memory variable whose value is set to represent the currentstocker position. Control then advances to step S24 where disk presenceflag D.FLAG(n) is set to 1. At step S25, controller 300 returns signalREAR to low (L) and sets signal FRONT to high (H). Control loops throughstep S26 until signal S.CLOSE goes low (L).

When signal FRONT goes high (H), timing belt 14 of disk transfermechanism 1001 begins rotating clockwise, moving disk D, d toward thefront of the disk player as the disk rolls counterclockwise. Disk D, dforces shutter 120 open toward the outside of the device. When signalS.CLOSE goes low (L), controller 300 returns signal FRONT to low (L) andsets signal REAR to high (H) at step S27. At step S28, controller 300waits again for signal S.CLOSE to change to high (H). As a result,timing belt 14 is again rotated counterclockwise, and disk D, d movedtoward the rear of housing 1000 as disk D, d rotates clockwise.

The movement of disk D, d causes shutter 120 to close, in turn causingsignal S.CLOSE to go high (H). At step S29, controller 300 beginscounting the output pulses (signal L. PULSE) from optical sensor 232 byincrementing an internal count variable once for each pulse of signal L.PULSE. At step S30, controller 300 checks to see if S.FLAG(n) has thevalue 1, indicating a small disk. If S.FLAG(n) is 0, indicating a largedisk, then, at step S31, a value of 6 is stored in an internal memoryvariable, SET. If S.FLAG(n) is 1, indicating a small-diameter disk, thencontroller 300 sets variable SET to 46 at step S32. At step S33,controller 300 compares the internal count variable with the value ofSET and loops if SET is higher than the internal count variable. Oncethe internal count variable reaches the value of SET, indicating thatdisk D (d) has reached position P2 (P7 for small disks), controlproceeds to step S34. At step S34 signal FRONT and signal REAR are sethigh (H) for a prescribed period (50 msec) electromagnetically brakingmotor 250, stopping its rotation abruptly.

As just described, the initial loading operation begins when a disk isinserted through insertion aperture 1A. The disk is drawn into the diskplayer and immediately brought partly outward again before being drawninward to the playback position P2/P7. This operation is performedbecause it allows the disk to register predictably and repeatably at thereference position defined by the closing of flap 120A. Since theplayback position is identified by measuring the movement of timing belt14, it is essential that the reference position be reliable to place thedisk in the playback position accurately. By bringing the disk out,under the control of the disk player, errors due to misregistration ofthe disk during initial insertion can be eliminated. For example, if theuser, in pushing the disk inside the disk player, forces flap 120A downprematurely, holds it open, or continues to push the disk in, such thatthe disk slips beyond the registration point (where flap 120A justcloses), the registration will be inaccurate and an unreliable referenceposition will result. Bringing the disk up to the registration point,under the control of the disk player, permits a repeatable and accuratereference position to be obtained before moving the disk to the internalposition. In this way, the disk is moved accurately to position P2 forlarge disks or P7 for small disks.

Control proceeds from step S34 to step S35. In steps S35-S39, controller300 moves sliding plate 75 from position DOWN-2 to position UP-1. Atstep S35, controller 300 sets signal P.UP to high (H) causing a drivevoltage to be output to move sliding panel 75 toward the right side ofhousing 1000. Control loops through step S36 until the output fromoptical sensor 237 (signal P. REF) goes low (L) indicating that slidingplate 75 has shifted to the reference position signalled by opticalsensor 237. Referring momentarily to FIG. 66, the reference position ofsliding plate 75 is just to the right of position DOWN-1, betweenposition DOWN-1 and position UP-1. At this position of sliding plate 75plate 40, optical mechanism 1006, is in the up position. Additionally,lower disk lock shaft 156 is in the unlock position.

After signal P. REF goes low, a process is begun in step S37, in whichan internal counter variable is incremented for each pulse of signal P.PULSE. The internal counter variable is compared with the number 27 atstep S38. Control loops through step S38 until the counter reaches 27.Referring momentarily to FIG. 66, during the loop through step S38,sliding plate 75 moves from the reference position to position UP-1,during which time base 40, with optical mechanism 1006, moves to the upposition and lower disk lock shaft 156 moves partially toward the lockposition. When the counter reaches 27, where sliding plate 75 reachesposition UP-1, control passes to step S39. At step S39, signal P.UP andsignal P.DWN go high for 50 msec, electromagnetically braking motor 251to stop it quickly. Disk D, d, which is in the playback position, ismounted on turntable 102, because of the movement of optical mechanism1006 to the up position. Thus, magnet 105 on turntable 102 attractsclamper 1009.

As shown in FIGS. 69 and 70, at step S40, controller 300 checks signalOUT from optical sensor 234 to determine if clamper holders 77L and 77Rare properly clamped about flange 115A. If clamper holders 77L and 77Rare properly clamped, as indicated by a low state of signal OUT, controlbranches to steps S41-S44 where sliding plate 75 is moved from positionUP-1 to position UP-2. At step S41, controller 300 outputs high (H) atsignal P.UP. At step S42, controller begins incrementing an internalcounter variable for each pulse of signal P. PULSE. Control loopsthrough step S43 until the counter variable reaches the value 18. Duringthe loop through step S43, sliding plate 75 moves toward the right ofthe disk player. When the counter variable reaches 18, indicating thatsliding plate 75 has reached position UP-2, control proceeds to stepS44. At step S44, signal P.UP and signal P.DWN are set to high (H) for50 msec, electromagnetically braking motor 251.

At position UP-2, optical mechanism 1006 is in the up position, andlower disk lock shaft 156 is entirely in the lock position shown in FIG.59. In addition, the lock on optical mechanism 1006 is released as shownin FIG. 33, and rack member 87 is brought to a position where it engageswith timing pulley 15 as shown in FIG. 29.

In steps S45-S49, controller 300 moves loading plates 81L and 81R fromthe support position POS.3 (for large disks or support position POS.2for small-diameter disks), where timing belt 14 and friction belt 12clamp disk D, d at its edge, to the open position POS.4 in which timingbelt 14 and friction belt 12 are moved apart to free the disk. First, atstep S45, controller 300 sets signal REAR to high (H), causing timingpulley 15 to rotate counterclockwise. As sliding plate 75 moves fromposition UP-1 to position UP-2, rack member 87 moves to cause gear 15Cto engage with rack 87D. Thus, as timing pulley 15 rotatescounterclockwise, loading plates 81L and 81R are moved laterally asdescribed above. At the instant that timing pulley 15 begins rotating,timing belt 14 is engaged with the outer perimeter of disk D, d. Thisapplies a clockwise rotation force to disk D, d, but, since disk D, d isheld on turntable 102, disk D, d remains in place despite the momentarytangential force applied to it.

When signal OUT goes low (L), controller 300 begins counting signal L.PULSE at step S47. Control loops through step S48 until the count valuereaches 11. During the loop, the lateral advancement of loading plates81L and 81R causes clamper holders 77L, 77R to separate. With theseparation of clamper holders 77L and 77R, the support on clamper 1009is released, permitting clamper 1009 to move under the force of magneticattraction, to turntable 102, clamping the disk. After the count valuereaches 11, the point at which loading plates 81L and 81R are at theirmost open (lateral) positions (POS.4), signal FRONT and signal REAR areset to high (H) for 50 msec at step S49. Thus, at step S49, anelectromagnetic braking force is applied to stop motor 250. Then, atstep S50, mode flag M.FLAG is set to STAND-BY and control is returned tothe main routine in FIG. 68.

An error resulting in misclamping by clamper 1009 can be caused byclamper support 115 moving upward, spreading apart clamper holders 77L,77R, and causing signal OUT to go high (H) as discussed above. If thisoccurs, control branches from step S40 to step S51 in which controller300 checks a number of times an error correction routine (the routine tobe described instantly) has been executed. In steps S52-S56, slidingplate 75 is returned from position UP-1 to position DOWN-2. At step S52,controller 300 sets signal P.DWN to high (H) causing sliding plate 75 tomove to the left of the disk player. Control then loops through step S53until signal P. REF goes high (H). When sliding plate 75 moves beyondposition UP-1, optical mechanism 1006 is lowered and lower disk lockshaft 156 is lowered and then raised again to the lock position. At apoint just short of position DOWN-1, signal P. REF goes high (H) andcontrol advances to step S54 where controller 300 begins counting signalP. PULSE. Control loops through step S55, until the count value reaches20, indicating that sliding plate 75 has reached position DOWN-2,whereupon control passes to step S56. At step S56, signal P.UP andsignal P.DWN are set to high (H) for 50 msec, electromagneticallybraking motor 251. At step S57, controller 300 sets signal FRONT to high(H), moving disk D, d toward the front of housing 1000. Control thenproceeds to step S26.

Thus, when a clamping error occurs, disk D, d is returned to the front(the position in which flaps 120A are open) and the registrationprocedure of steps S26-S28 performed again, finally bringing the diskback to the playback position. This procedure serves to eliminateoffsets in the disk playback position caused by vibration or othercauses, resulting in improved reliability in clamping of disk D, d.

Referring now also to FIG. 71, if after three consecutive executions ofthe error correction routine beginning at step S51, misclamping stilloccurs, controller 300 proceeds from step S51 to step S58. At step S58,signal P.DWN is set to high (H) causing sliding plate 75 to begin movingfrom position UP-1 to position DOWN-2. The description of steps S59-S62is omitted since the details are identical to those of steps S53-S56described above. In steps S63-S66, controller 300 brings disk D to theeject position P6 shown in FIG. 19 (small-diameter disk d is brought toeject position P9, shown in FIG. 24). At step S63, controller 300 setssignal FRONT to high (H). Then, at step S64, controller 300 beginscounting signal L. PULSE. Control loops through step S65 until the countvalue reaches 105. When signal FRONT goes high (H), timing belt 14 ofdisk transfer mechanism 1001 starts moving disk D, d toward the front ofthe disk player. As disk D, d moves toward the front, it rollscounterclockwise along friction belt 12. When the count value reaches105, at which point disk D,d is at the eject position, control passes tostep S66. At step S66, signal FRONT and signal REAR are set to high (H)for 50 msec, electromagnetically braking motor 251. Controller 300 thensets mode flag M.FLAG to EJECT at step S67, and control returns to themain routine.

Once disk D, d, at the eject position, is removed, spring 127 bringsloading plates 81L and 81R toward each other to disk receiving positionPOS.1 (FIG. 13). The movement of loading plate 81L causes the outputfrom optical sensor 236, signal IN, to go low (L). Control branches fromthe main loop at step S3 when disk D, d is at the eject position(because flag M.FLAG is set to EJECT as described above) to step S4.Control proceeds to step S11 if signal IN is low, indicating that thedisk has been removed from the eject position. Controller 300 thenproceeds to steps S11-S13. D.FLAG(n) and S.FLAG(n) are to 0 in steps S11and S12, respectively. M.FLAG is set to READY in step S13. Then,controller 300 returns to the main loop (steps S1-S10) at step S5 andcontinues to monitor for disk insertion, disk removal, eject/load keyactuation, read commands from the computer, or an absence of a readcommand over a prescribed interval.

The following is a description of the control sequences initiated whenone of E/L key 1 through E/L key 4 is pressed. Briefly, when an E/L keywith the same number as the current stocker position is pressed,controller 300 brings the disk, stored in that stocker position, to theeject position if a disk D, d is present at the stock position or theplayback position. If a disk D, d is in the eject position, that disk isbrought to the playback position. If an E/L key is entered having adifferent number from the current stocker position, and if there is adisk D, d in the eject position or the playback position, thencontroller 300 moves that disk to a stock position, moves stocker 1011to the position corresponding to the E/L key pressed, and brings thespecified disk to the eject position. If no disk D, d is present in thespecified position, then controller 300 stores the disk that is in theeject position or the playback position, in stocker 1011. After stocker1011 is transferred to the specified position, loading plates 81L and81R are brought to the disk receiving position.

When E/L key 1-E/L key 4 is pressed, controller stores a correspondingnumber (from 1 to 4) in an internal variable, m. If E/L key 1 ispressed, control branches from step S5 to step S14 where the value 1 isstored in internal memory variable m and control passes to JOB E/L. IfE/L key 2 is pressed, control branches from step S6 to step S15 wherethe value 2 is stored in internal memory variable m and control passesto JOB E/L. If E/L key 3 is pressed, control branches from step S7 tostep S16 where the value 3 is stored in internal memory variable m andcontrol passes to JOB E/L. If E/L key 4 is pressed, control branchesfrom step S8 to step S17 where the value 4 is stored in internal memoryvariable m and control passes to JOB E/L.

At step S70, controller 300 checks to see if M.FLAG is set to STOCK. IfM.FLAG is set to STOCK, control proceeds to step S71, where controller300 checks to see if the values for m and n are identical, therebydetermining whether the E/L key pressed corresponds to the currentstocker position. If the values are identical, controller 300 executessteps S86-S92, in which loading plates 81L and 81R are moved from openposition POS.4 to a position just short of support position POS.3 (orsupport position POS.2 for small-diameter disks). At step S86,controller 300 sets signal FRONT to high (H). At step S87, controller300 begins counting signal L. PULSE. Control then passes from step S88to S90, if S.FLAG is 1, indicating a small-diameter disk. Control passesfrom step S88 to S89, if S.FLAG is 0, indicating a large-diameter disk,or to step S90 if S.FLAG 1, indicating a small-diameter disk. In stepS90, 75 is stored in internal variable SET. In step S89, 12 is stored ininternal variable SET. Control loops through step S91 until the countvalue reaches the SET value. During the time signal FRONT is high (H)(during the looping through step S91), timing pulley 15 is rotatedcounterclockwise, causing it to move to the right along rack 87D. Thusloading plates 81L and 81R are moved medially together. As loadingplates 81L and 81R are brought toward each, clamper holders 77L and 77Rconverge under the urging of spring 128 so that support mechanism 1010lifts flange 115A of clamper 1009. At step S92, motor 250 iselectromagnetically braked for 50 msec by setting signal FRONT andsignal REAR to high (H). Note that the values 12 and 75 are just shortof the values used to count to positions POS.3 and POS.2, respectively.The reason for using a value in SET that is smaller than the pulse countrequired to separate loading plates 81L and 81R exactly enough tosupport the disk is that if detection errors cause a pulse to be missed,the spacing will still be small enough to support the disk.

Controller 300 moves sliding plate 75 from position UP-2 to positionDOWN-1 in steps S93-S97. At step S93, controller 300 outputs a high (H)level at signal P.DWN, causing motor 251 to begin moving sliding plate75 toward the left side of housing 1000. Control loops through step S94until signal P. REF goes high (H), indicating that sliding plate 75 hasarrived at the reference position. Early in the traverse of slidingplate 75 from UP-2 to DOWN-1, clamper lock mechanism 1007 locks opticalmechanism 1006 to base 40 and loading plate open/close mechanism 1004disengages rack member 87 from timing pulley 15. As soon as rack member87 disengages timing pulley 15, spring 127 pulls loading plates 81L and81R together so that timing belt 14 and friction belt 12, of disktransfer mechanism 1001, are brought to positions in which disk D, d issupported between them. The motion of sliding plate 75 causes lower disklock shaft 156 to descend, and when sliding plate 75 moves beyond UP-1,optical mechanism 1006 is moved downward. Control passes to step S95 inwhich controller 300 begins counting pulses of signal P. PULSE. Controlloops through step S96 until 3 pulses are counted indicating thatsliding plate 75 has arrived at position DOWN-1. At step S97, signalP.UP and signal P.DWN are set to high (H) for 50 msec, so that motor 251is electromagnetically braked. At position DOWN-1 of sliding plate 75,optical mechanism 1006 is lowered and lower disk lock shaft 156 islowered to the unlocked position. This permits disk transfer withinstocker 1011.

In steps S98-S101, controller 300 brings a stored disk D, d from stocker1011 to the eject position. At step S98, controller 300 sets signalFRONT to high (H) to start motor 250 to bring disk d, D toward the frontof the disk player. At step S99, controller 300 begins counting signalL. PULSE. Control loops through step S100, until the count value reaches259 indicating the arrival of disk D, d at the eject position. At stepS101, signal FRONT and signal REAR are set to high (H) for 50 msecelectromagnetically braking motor 250.

In steps S102-S108, controller 300 moves sliding plate 75 from positionDOWN-1 to position DOWN-2. At step S102, controller 300 sets signal P.UPto high (H) causing motor 251 to begin moving sliding plate toward theright side of housing 1000. Control loops through step S103, untilsignal P. REF goes low (L), indicating the arrival of sliding plate 75at the reference position. At step S104 controller 300 sets signal P.UPto low (L) and signal P.DWN to high (H) to cause motor 251 to beginmoving sliding plate 75 toward the left side of housing 1000. Controlloops through step S105 until signal P. REF goes high (H). At step S106,controller 300 begins counting signal P. PULSE. Control loops throughstep S107 until the count reaches 20 indicating that sliding plate 75has arrived at position DOWN-2. At step S108, signal P.UP and signalP.DWN are set to high (H) for 50 msec, electromagnetically braking motor251. At step S109, M.FLAG is set to EJECT, and control returns to themain routine of FIG. 68.

If values for m and n are not identical at step S71, control proceeds tostep S72 where controller 300 checks the output D.LOCK from opticalsensor 229, which indicates the position of lower disk lock shaft 156.If signal D.LOCK is low (L), indicating that lower disk lock shaft 156is at the lock position, control passes to step S73 where controller 300moves stocker 1011 to position POS.m (Recall that m indicates the E/Lkey pressed). Thus, for example, if E/L key 4 is pressed, stocker 1011is moved to position POS(4). Once stocker 1011 has been brought to thespecified position, controller 300 sets internal memory variable n(which indicates the current stocker position) equal to m.

At step S75, controller 300 checks to see if D.FLAG(n) is 1 to confirmwhether a disk is at position POS(n). If D.FLAG(n) is 1, indicating thatthere is a disk in position n of stocker 1011, controller 300 proceedsto steps S86-S92 (described above) whereupon loading plates 81L and 81Rare moved from the open position POS.4 to the support position POS.3 (orposition POS.2 for small-diameter disks), and disk D, d is brought tothe eject position.

If, at step S75, D.FLAG(n) is 0, controller 300 moves loading plates 81Land 81R from open position POS.4 to disk receiving position POS.1 insteps S76-S79. At step S76, controller 300 sets signal FRONT to high(H), whereupon timing pulley 15 starts rotating clockwise moving timingpulley 15, and loading rack 81L, along rack member 87. At step S77,controller 300 begins counting signal L. PULSE. Control loops throughstep S78 until the count value reaches 82. The rotation of timing pulley15 with gear 15C engaged with rack 87D, causes loading plates 81L and81R to move medially together. As loading plates 81L and 81R close,spring 128 brings clamper holders 77L and 77R together so that clampersupport mechanism 1010 supports flange 115A. When the count valuereaches 82, indicating that loading plates 81L and 81R have arrived at aposition just short of disk receiving position POS.1, control passes tostep S79. At step S79, signal FRONT and signal REAR are set to high (H)for 50 msec, electromagnetically braking motor 250.

In steps S80-S84, controller 300 moves sliding plate 75 from positionUP-2 to position DOWN-2. The details of this operation are similar tothe operation in steps S52-S56, described above, therefore, the detailsare not repeated. Note that even though the result of the operation ofsteps S80-S84 is to move from UP-2 to DOWN-2, while that of stepsS52-S56 is to move from UP-1 to DOWN-2, the procedure is identical, ascan be seen by comparing FIGS. 68 and 72. At step S85, controller 300sets M.FLAG to READY and control returns to the main routine.

In step S72, if D.LOCK is high (H), indicating that lower disk lockshaft 156 is not at the lock position, controller 300 proceeds to stepS110. As described above, this situation indicates misalignment of thedisk because, if the disk is not accurately positioned, lower disk lockshaft 156 is blocked by the disk. As described above, the correctionmechanism for this condition is to transport the disk to a positionwhere shutter 120 is opened and then moving it inward again until thereference position, at which shutter 120 just closes, is reached. DiskD,d is then moved again to the stock position. At step S110, controller300 checks the number of retry attempts made. In steps S111-S117,operations identical to those in steps S86-S92 are carried out, withloading plates 81L and 81R being moved from the open position POS.4 tosupport position POS.3 (for large disks or POS.2 small disks). Then, insteps S118-S122, operations identical to those in steps S93-S97 arecarried out, with sliding plate 75 being moved from position UP-2 toposition DOWN-1, and optical mechanism 1006 and lower disk lock shaft156 being moved to the down position and the unlock position,respectively.

In steps S123-S132, controller 300 follows a procedure that is similarto steps S57 and S26-S34 where disk D, d is brought to a position whereshutter 120 is opened and then back into the disk player. However, inthis case, the disk is brought to the stock position instead of positionP2 (or P7 for small disks). This procedure is as follows. First, at stepS123, controller 300 sets signal FRONT to high (H), starting disktransfer mechanism 1001 so that it moves disk D, d toward the front ofhousing 1000. Control loops through step S124 until signal S.CLOSE goeslow (L), indicating the disk has pushed shutter 120 open. At step S125,controller 300 sets signal FRONT to low (L) and signal REAR to high (H)to begin moving disk D, d rearward. Control then loops through step S126until signal S.CLOSE changes to high (H) again, indicating that shutter120 has just closed in response to the movement of disk D, d. Aftersignal S.CLOSE goes high (H), controller 300 begins counting signal L.PULSE at step S127. Controller 300 checks S.FLAG(n) at step S128 and ifit is 1, indicating a small disk, the value 200 is stored in internalvariable SET at step S130, otherwise, the value 160 is stored in SET.Control loops through step S131 until the count value reaches the valueof SET indicating the disk has reached the stock position. At step S132,controller 300 sets signal FRONT and signal REAR to high (H) for 50msec, electromagnetically braking motor 250.

In steps S133-S137, controller 300 moves sliding plate 75 from positionDOWN-1 to position UP-2. First, at step S133, controller 300 sets signalP.UP to high (H). Control loops through step S134 until signal P. REFgoes low (L) as sliding plate 75 moves rightwardly. When signal P. REFgoes low (L), controller 300 begins counting signal P. PULSE at stepS135. Control loops through step S136 until the count value reaches 45,indicating that sliding plate 75 has reached position UP-2, and controlpasses to step S137. At step S137, signal P.UP and signal P.DWN are setto high (H) for 50 msec, electromagnetically braking motor 251.

Steps S138-S142 perform the same operations as steps S45-S49 in whichcontroller 300 moves loading plates 81L and 81R to open position POS.4.Since this procedure is described in detail above, it is not repeatedhere. After step S142, controller 300 passes to step S72 where D.LOCK ischecked. If the disk lock error occurs after the retry operationdescribed above is repeated three times, controller 300 proceeds fromstep S110 in FIG. 74 to step S86 in FIG. 72 and Disk D, d is brought tothe eject position.

When an E/L key is entered during stand-by mode, a disk, in the storagelocation corresponding to the E/L key pressed, is retrieved and broughtto the playback position. For example, if E/L key 1 is pressed instand-by mode, controller 300 sets constant m to 1 at step S14 asdescribed above. Controller 300 then proceeds to step S70 (FIG. 72) tostep S150 (FIG. 75), where M.FLAG is checked. If M.FLAG is set toSTAND-BY, as in this case, controller 300 proceeds to step S151. If mand n are identical, indicating the current stocker position correspondsto the E/L key pressed, control passes from step S151 to step S152.Steps S152-S157, perform the same operations as steps S86-S92.Therefore, in steps S152-S157, loading plates 81L and 81R are moved fromopen position POS.4 to a position just short of support position POS.3(for large disks, or POS.2 for small disks). Control then passes to stepS158.

Steps S158-S162, perform the same operations as steps S52-S56 and thedetails are, therefore, not repeated. Thus, in steps S158-S162,controller 300 moves sliding plate 75 from position UP-2 to positionDOWN-2. In steps S163-166, controller 300 brings disk D, from theplayback position, to the eject position following a procedure identicalto that of steps S63-S66 and the details are, therefore, not repeated.At step S169, M.FLAG is set to EJECT, and control returns to the mainroutine.

If, at step S151 described above, the values for m and n differ,controller 300 proceeds to step S170 (FIG. 76). Steps S170-S210 performthe same operations as steps S11-S142. Thus, loading plates 81L and 81Rare moved from open position POS.4 to a position just short of supportposition POS.3 (for large disks, POS.2 for small-diameter disks);sliding plate 75 is moved from position UP-2 to position DOWN-1; disk D,d, is moved from the playback position, to the stock position; slidingplate 75 is moved from position DOWN-1 to position UP-2; and loadingplates 81L and 81R are moved to the open position POS.4. Controller 300then proceeds to step S72 (FIG. 72). From step S72, operation proceedsthrough steps S73-S92 where stocker 1011 is moved to POS(m) and loadingplates 81L and 81R close around the disk. Control proceeds to S93through S109 where sliding plate 75 is moved from UP-2 to DOWN-1lowering lower disk lock shaft 156 to unlock the disk and loweringoptical mechanism 1006 to clear the way for movement of the disk. Insteps S98-S109, the disk is moved to the eject position and lower disklock shaft 156 locked again. Then control returns to the main routine.

Referring to FIGS. 72-79, when one of the E/L keys is pressed while thedisk player is in the EJECT mode (M.FLAG=EJECT), controller 300 setsmemory variable m equal to a value corresponding the E/L key pressed.For example, if E/L key 3 is pressed (step S7), the value 3 is stored ininternal memory variable m (step S16). Controller 300 then proceeds fromthe main control flow diagram to step S220 in FIG. 78 via step S70 ofFIG. 72 and step S150 of FIG. 75. At step S220, the status of M.FLAG ischecked. In this case, M.FLAG=EJECT, so control to proceeds to stepS221. At step S221 control branches step S20 if the values of m and nare the same, indicating that the E/L key pressed corresponds to thecurrent stocker position. In steps S20-S40 to S41-S50, disk D, d isbrought from the eject position to the playback position, clamped,loading plates 81L and 81R retracted to release disk D, d, the diskplayer placed in standby mode, and control returned to the main routine.

If, in step S221, the values for m and n are not identical, controller300 proceeds through steps S222-S236, which perform the same operationsas steps S20-S34 described earlier. That is, in steps S222-S236, disk D,d is brought from the eject position to the playback position. In stepsS237-S240, controller 300 moves sliding plate 75 from position DOWN-2 toposition DOWN-1 as follows. At step S237 (FIG. 79), controller 300outputs high (H) at signal P.UP causing sliding plate 75 to begin movingto the right side of housing 1000. At step S238, controller 300 beginscounting signal P. PULSE. Control loops through step S107 until thecount value reaches 17 indicating sliding plate 75 has arrived atposition DOWN-1. At step S240, signal P.UP and signal P.DWN are set high(H) for 50 msec, electromagnetically braking motor 251. As a result ofsliding plate 75 being moved to position DOWN-1, lower disk lock shaft156 is in the unlock position, permitting disk D, d to be moved to thestock position.

Steps S241-S260 perform the same functions as steps S182-S210 describedabove. That is, controller 300 moves disk D, d, from the playbackposition to the stock position; sliding plate 75 from position DOWN-1 toposition UP-2; and loading plates 81L and 81R to open position POS.4.Control then passes to step S72 (FIG. 72). From step S72, operationproceeds through steps S73-S92 where stocker 1011 is moved to POS(m) andloading plates 81L and 81R closed around the disk. Then control proceedsto steps S93 through S197 where sliding plate 75 is moved from UP-2 toDOWN-1 lowering disk lock shaft 156 to unlock the disk and loweringoptical mechanism 1006 to clear the way for movement of the disk. Then,in steps S98-S109, the disk is moved to the eject position and lowerdisk lock shaft 156 locked again. Finally control returns to the mainroutine.

When an externally connected computer 303 (FIG. 67) sends a readcommand, control proceeds from step S9 to step S18 in the main routineshown in FIG. 68. The various mechanisms are controlled, as describedabove, to bring the selected disk D, d to the playback position and thestand-by mode activated. The read command for the specified file is sentto signal processing circuit 307 and servo circuit 308. The read signalgenerated by optical pickup amp 2 is sent to signal processing circuit307 via RF amp 309. After EFM demodulation, deinterleaving, errorcorrection and other usual operations are performed, the signal is sentto externally connected computer 303 via interface circuit 302. Once thereading of the specified file is complete, controller 300 stops signalprocessing circuit 307 and servo circuit 308. M.FLAG is then set againto STAND-BY and controller 300 returns to the main routine.

Referring to FIGS. 68, 80, and 81, if, while in stand-by mode,controller 300 does not receive a read command from computer 303 for aprescribed interval, for example, 10 minutes, then controller 300proceeds from step S10 to step S19 to step S270 (FIG. 80). StepsS270-S301, perform the same operations as steps S111-S142, describedabove. Thus,loading plates 81L and 81R are moved from open positionPOS.4 to a position just short of support position POS.3 (for largedisks, or position POS.2 for small-diameter disks); sliding plate 75 ismoved from position UP-2 to position DOWN-1; disk D, d, is brought fromthe playback position, to the stock position; sliding plate 75 isbrought from position DOWN-1 to position UP-2; and loading plates 81Land 81R are moved to open position POS.4. Control branches from stepS302 to step S303 if signal D.LOCK is low (L) In step S303, M.FLAG isset to STOCK at step S303. Control then returns to the main routine.

If signal D.LOCK does not pass to a low state at step S302, indicatingthat it is misaligned, then controller 300 proceeds to step S304 (FIG.81). In steps S304-S335, controller 300 moves the disk toward the frontuntil shutter 120 opens and then returns it to a point where shutter 120closes again, thereby registering the disk again. The disk is thenbrought again to the stock position. Controller 300 returns to step S302shown in FIG. 80, and signal D.LOCK is checked again. The details of theoperations performed in steps S304-S336 are identical to the operationsperformed in steps S110-S142 described above, so the description isomitted here.

Referring to FIG. 83, a second embodiment of a support for timing belt14 provides smoother operation. An endless teflon sheet 400 having a lowfriction coefficient is wrapped around the peripheral surface of a guidewall 10D, which supports timing belt 14. Thus, when timing belt 14 isrevolved, teflon sheet 400 lubricates the adjacent sliding surfaces oftiming belt 14 and guide wall 10D. This provides smoother slidingcompared to direct contact between timing belt 14 and guide wall 10D. Ofcourse, the teflon sheet can be made from another material having a lowfriction coefficient.

Referring to FIG. 84, a third embodiment of drive-side disk guide 1002,also provides low friction support for timing belt 14. In thisembodiment, small-diameter rollers 401 alternate with large-diameterrollers 402 on the inside of timing belt 14. The rollers are supportedon shafts 403. Inward flexure of timing belt 14 could also beeffectively prevented by using just small-diameter rollers 401, but suchan arrangement has poor potential from a production cost standpoint. Byusing large rollers and small rollers in an alternating pattern, it ispossible to achieve nearly the sam result with fewer components, therebyreducing production cost while effectively preventing inward flexure oftiming belt 14.

Referring to FIG. 85, a fourth embodiment of drive-side disk guide 1002also provides low friction support of timing belt 14. In thisembodiment, the distances between shafts 403 of rollers 401 are madesmaller than the diameter of rollers 401. Thus, rollers 401 overlap eachother. This decreases the interval between support points (the points ofcontact between rollers 401 and the inside surface of timing belt 14)thereby improving the support and straightness of timing belt 14.

Referring to FIG. 86, although the embodiment of the invention describedabove is a horizontal configuration in which CD's are inserted, stored,and transported with their recording surfaces horizontal, an alternativeembodiment could be a vertical configuration. In a verticalconfiguration, timing belt 14 would be optimally located on the upperside, and disk D would be inserted from insertion aperture 1A in frontpanel 1. Disk D would then rotate with its top moving toward the back ofthe disk player as it is fed and rotated. This would provide a naturalfeel to the user as opposed to having to push the bottom in faster thanthe top of the CD.

Although the above embodiments describe a CD player with a built-inchanger mechanism, many aspects of the invention may be applied to asingle disk player as well with or without internal CD storagecapability.

Although in the embodiments described, the disk transfer mechanism has amoving drive belt and a fixed disk guide causing the disk to roll whileit is transported, it is also possible that both sides of the disk couldbe supported with moving drive belts. In the latter configuration, thedisk would not roll during transport.

Although in the embodiments described above, a drive belt and a diskguide are interconnected by a rack and pinion mechanism so that theyeach move apart and together with no net movement between them. Thus,when a disk is inserted, they each move the same distance. However, itwould also be possible, for example, to fix the drive belt and have onlythe disk guide move responsively to the insertion of a disk. In thiscase, depending on whether the inserted disk is a 120 mm disk or an 80mm disk, the center of the disk would track a different line inside thedisk player. However, either type of disk could be accommodated byemploying a read mechanism capable of moving laterally in response tothe size of disk inserted.

Although in the embodiments described above, a disk guide 11E is locatedat an end of friction belt 12, it is clear from the present disclosure,that a disk guide 11E could be located at the end of timing belt 14.This would achieve a similar effect and advantage as the disk guidedescribed above. Either a single disk guide could be located at arespective end of either the friction belt or the timing belt or twodisk guides could be used, one for each of the friction belt and thetiming belt. Any of the above configurations are considered to be withinthe bounds of the present invention and enabled by the presentdisclosure.

As described above, the present invention allows transporting of disksregardless of the diameter of the disk since the distance between thepair of disk transporting means, when a disk is not inserted, is smallerthan the diameter of the disk to be inserted.

In the above embodiment, the present invention is implemented in achanger-type disk player. However, the present invention is notrestricted to this, and can be implemented in a single disk player thatis not a changer-type player.

In the embodiments described above, the disk is transferred by a drivebelt system. However it is clear from the description that the inventioncan be applied to disk players with other transport mechanisms. Forexample, a device the holds the disk by the disk edges by means forrollers or a movable tray-type support could be used. Such alternativeembodiments are considered to be in the scope of the present invention.

In the embodiments described above, the clamper is moved and held to theturntable by means of magnetic attraction. However it is clear from thedescription that the invention can be applied to disk players thatemploy other mechanisms for moving a clamper to the turntable and urgingit against the turntable surface. For example, the lifting mechanismcould also incorporate a spring or other mechanical means for forcingthe clamper toward the turntable, with a bearing to isolate the meansfor forcing from the rotating clamper, as well as the means for liftingthe clamper. Such alternative embodiments are considered to be in thescope of the present invention.

Having described preferred embodiments of the invention with referenceto the accompanying drawings, it is to be understood that the inventionis not limited to those precise embodiments, and that various changesand modifications may be effected therein by one skilled in the artwithout departing from the scope or spirit of the invention as definedin the appended claims.

What is claimed is:
 1. A disk playback device, comprising:a turntablehaving a disk mounted thereon; a clamper, on a side of said diskopposite said turntable, for clamping said disk to said turntable;supporting means for supporting said clamper at a first position awayfrom said disk prior to a clamping of said disk; and said supportingmeans incliding means for releasing said clamper, whereby said clamperis freed to move toward said disk; a chassis; said turntable and saidsupporting means being connected to chassis; said disk having arecording surface; said supporting means including a first engagementelement being movably connected to said chassis and movable in directionparallel to said recording surface; said supporting means also includinga second engagement element connected to said clamper; said firstengagement element engaging and moving said second engagement elementwhen said first engagement element is moved in a first direction, saidmoving of said second engagement element being such that said clamper ismoved away from said disk; and said first engagement element releasingsaid second engagement element when said first engagment element ismoved in a direction opposite said first direction; said firstengagement element including a lifting surface substantially inclinedwith respect to said recording surface; said second engagement elementbeing guided by said lifting surface to move said second engagmentelement and, thereby, move said clamper away from said disk; said firstengagement element including a detecting surface substantially inclinedwith respect to said recording surface such that said detecting surfaceand said lifting surface form oppositely directed angles with respect tosaid recording surface; said disk having a center holes; a spindle onsaid turntable for insertion into said center hole when said spindle isaligned with said hole; means for inserting said spindle in said centerhole; means for pressing a portion of said clamper against saiddetecting surface when said spindle hole is not aligned with said centerhole.
 2. A disk player, comprising:a turntable having a disk mountedthereon; a clamper, on a side of said disk opposite said turntable, forclamping said disk to said turntable; supporting means for supportingsaid clamper at first position away from said disk prior to a clampingof said disk; and said supporting means including means for releasingsaid clamper, whereby said clamper is freed to move toward said disk;said disk having a center hole; a spindle on said turntable forinsertion into said center hole when said spindle is aligned with saidhole; means for inserting said spindle in said center hole; and meansfor detecting a misalignment between said center hole and said spindleby detecting a movement of said clamper; said disk has a back surfaceopposite a recording surface; said means for inserting moves saidspindle toward said disk to insert said spindle and presses said spindleagainst said recording surface when said center hole is not aligned withsaid spindle; said means for insertinig is operated to insert saidspindle in said center hole prior to a release of said clamper; and saidmeans for detecting a misalignment including means for detecting anirregular movement of said clamper prior to said release of saidclamper, said irregular movement being caused by said back surfacepushing against said clamper as a result of a pressing of said spindleagainst said recording surface.
 3. A disk player, comprising:a turntablehaving a disk mounted thereon; a clamper, on a side of said diskopposite said turntable, for clamping said disk to said turntable;supporting means for supporting said clamper at a first position awayfrom said disk prior to a clamping of said disk; said supporting meansincluding releasing said clamper, whereby said clamper is freed to movetoward said disk; said disk having a center hole; a spindle on saidturntable for insertion into said center hole when said spindle isaligned with said hole; means for inserting said spindle in said centerhole; and means for detecting a misalingnment between said center holeand said spindle by detecting a movement of said clamper; said disk hasa back surface opposite said recording surface; said means for insertingmoves said spindle toward said disk to insert said spindle and pressessaid spindle against one of said recording surface and said back surfacewhen said center hole is not aligned with said spindle; said means forinserting is operated to insert said spindle in said center hole priorto a release of said clamper; and said means for detecting amisalignment including means for detecting an irregular movement of saidclamper prior to said release of said clamper, said irregular movementbeing caused by the other of said recording surface and said backsurface pushing against said clamper as a result of a pressing of saidspindle against said one of said recording surface said back surface.